Hiding the Decline

by Judith Curry

To date, I’ve kept Climate Etc.  a “tree ring free zone,” since the issues surrounding the hockey stick are a black hole for conflict and pretty much a tar baby, IMO.  Further, paleoproxies are outside the arena of my personal research expertise, and I find my eyes glaze over when I start reading about bristlecones, etc.  However, two things this week have changed my mind, and I have decided to take on one aspect of this issue: the infamous “hide the decline.”

The first thing that contributed to my mind change was this post at Bishop Hill entitled “Will Sir John condemn hide the decline?”, related to Sir John Beddington’s statement:  It is time the scientific community became proactive in challenging misuse of scientific evidence.

The second thing was this youtube clip of physicist Richard Muller (Director of the Berkeley Earth Project), where he discusses “hide the decline” and vehemently refers to this as “dishonest,” and says “you are not allowed to do this,” and further states that he intends not to read further papers by these authors (note “hide the decline” appears around minute 31 into the clip).  While most of his research is in physics, Muller has also published important papers on paleoclimate, including a controversial paper that supported McIntyre and McKitrick’s analysis.

The question I am asking myself is what is my role as a scientist in challenging misuses of science (as per Beddington’s challenge)?  Why or why not should I personally get involved in this?   Is hiding the decline dishonest and/or bad science?

Explanations, interpretations, and misrepresentations of “hide the decline”

Realclimate describes the issue as follows:

Phil Jones in discussing the presentation of temperature reconstructions stated that “I’ve just completed Mike’s Nature trick of adding in the real temps to each series for the last 20 years (ie from 1981 onwards) and from 1961 for Keith’s to hide the decline.” The paper in question is the Mann, Bradley and Hughes (1998) Nature paper on the original multiproxy temperature reconstruction, and the ‘trick’ is just to plot the instrumental records along with reconstruction so that the context of the recent warming is clear. Scientists often use the term “trick” to refer to a “a good way to deal with a problem”, rather than something that is “secret”, and so there is nothing problematic in this at all. As for the ‘decline’, it is well known that Keith Briffa’s maximum latewood tree ring density proxy diverges from the temperature records after 1960 (this is more commonly known as the “divergence problem”–see e.g. the recent discussion in this paper) and has been discussed in the literature since Briffa et al in Nature in 1998 (Nature, 391, 678-682). Those authors have always recommend not using the post 1960 part of their reconstruction, and so while ‘hiding’ is probably a poor choice of words (since it is ‘hidden’ in plain sight), not using the data in the plot is completely appropriate, as is further research to understand why this happens.

Steve McIntyre has quite a different intepretation.  With regards to Briffa 1998:

Despite relatively little centennial variability, Briffa’s reconstruction had a noticeable decline in the late 20th century, despite warmer temperatures. In these early articles [e.g. Briffa 1998], the decline was not hidden.

For most analysts, the seemingly unavoidable question at this point would be – if tree rings didn’t respond to late 20th century warmth, how would one know that they didn’t do the same thing in response to possible medieval warmth – a question that remains unaddressed years later.

Briffa et al 1998a (Nature 391): During the second half of the twentieth century, the decadal-scale trends in wood density and summer temperatures have increasingly diverged as wood density has progressively fallen. The cause of this increasing insensitivity of wood density to temperature changes is not known, but if it is not taken into account in dendroclimatic reconstructions, past temperatures could be overestimated.

With regards to the IPCC TAR:

In a post-mortem a few weeks later, Coordinating Lead Author Folland wrote that, although a proxy diagram was “a clear favourite for the Policy Makers summary”, the Briffa reconstruction “dilutes the message rather significantly”, adding that this was “probably the most important issue to resolve in Chapter 2 at present”. Mann wrote that “everyone in the room” agreed that the Briffa series was a “potential distraction/detraction from the reasonably consensus viewpoint we’d like to show”. Briffa recognized there was “pressure to present a nice tidy story as regards ‘apparent unprecedented warming in a thousand years or more ’”, but expressed many caveats, in particular that the proxies were not responding the way that they were supposed to and that that the recent warmth was “probably matched” 1000 years ago.

Otherwise, the skeptics have an field day casting doubt on our ability to understand the factors that influence these estimates and, thus, can undermine faith in the paleoestimates. I don’t think that doubt is scientifically justified, and I’d hate to be the one to have to give it fodder! (Mann Sep 22, 0938018124.txt)

And on and on, McIntyre provides substantial documentation for his analysis.

With this context, the media has continued to completely misrepresent the situation, being inconsistent with either the RC or McIntyre analyses.  Tim Lambert provides a summary of recent inaccurate media statements, here is a common example:

4 February 2011, Investor’s Business Daily:  The ClimateGate scandal was a direct result of scientists — and we use the term loosely — at Britain’s Climate Research Unit and others, such as Michael Mann, conspiring to manipulate data to “hide the decline” in global temperatures.

The obvious inaccuracy of such statements and their easy refutation distracts from addressing the substantive issues raised by McIntyre.

Bad science and/or dishonesty?

There is no question that the diagrams and accompanying text in the IPCC TAR, AR4 and WMO 1999 are misleading.  I was misled.  Upon considering the material presented in these reports, it did not occur to me that recent paleo data was not consistent with the historical record.  The one statement in AR4 (put in after McIntyre’s insistence as a reviewer) that mentions the divergence problem is weak tea.

It is obvious that there has been deletion of adverse data in figures shown IPCC AR3 and AR4, and the 1999 WMO document.  Not only is this misleading, but it is dishonest (I agree with Muller on this one).  The authors defend themselves by stating that there has been no attempt to hide the divergence problem in the literature, and that the relevant paper was referenced.  I infer then that there is something in the IPCC process or the authors’ interpretation of the IPCC process  (i.e. don’t dilute the message) that resulted in the scientists into deleting the adverse data in these diagrams.

McIntyre’s analysis is sufficiently well documented that it is difficult to imagine that his analysis is incorrect in any significant way.  If his analysis is incorrect, it should be refuted.  I would like to know what the heck Mann, Briffa, Jones et al. were thinking when they did this and why they did this, and how they can defend this, although the emails provide pretty strong clues.  Does the IPCC regard this as acceptable?  I sure don’t.

Can anyone defend “hide the decline”?  I would much prefer to be wrong in my interpretation, but I fear that I am not.

State of the paleoreconstruction science

This raises the issue as to whether there is any value at all in the tree ring analyses for this application, and whether these paleoreconstructions can tell us anything.  Apart from the issue of the proxies not matching the observations from the current period of warming (which is also the period of best historical data), there is the further issue as to whether these hemispheric or global temperature analyses make any sense at all because of the sampling issue.  I am personally having a difficult time in seeing how this stuff has any credibility at the level of “likely” confidence levels reported in the TAR and AR4.

I am really hoping that the AR5 will do a better job of providing a useful analysis and assessment of the paleodata for the last millennium.  However I am not too optimistic. There was another Workshop in Lisbon this past year (Sept 2010), on the Medieval Warm Period.  The abstracts for the presentations are found here.  No surprises, many of the usual people doing the usual things.

I view paleoclimate as a really important subject in the context of understanding climate change.  I have no interest in warmest year or warmest decade; rather we need to understand the magnitude and characteristics and causes of natural climate variability over the current interglacial, particularly the last 2000 years.  I’m more interested in the handle than the blade of the hockey stick.  I also view understanding regional climate variations as much more important than trying to use some statistical model to create global average anomalies (which I personally regard as pointless, given the sampling issue).

I don’t want to throw the baby away with the bath water here.  But this whole issue is a big problem for the science and has been an enormous black eye for the credibility of the IPCC and climate science.   I suspect that many denizens will be on board with my assessment and are very familiar with McIntyre’s analysis.  I would be particularly interested in hearing from any defenders of these global paleotemperature analyses by Mann et al.

If there is a problem, lets get to the bottom of it and fix it.

1,472 responses to “Hiding the Decline

  1. Efforts to hide the decline largely destroyed public credibility in climate science.

    But the pawns involved are not to blame. The responsibility lies much closer to the top of the research food chain.

    • Efforts to hide the decline largely destroyed public confidence in climate science.

      • Prove it ,Oliver. I doubt it ‘largely destroyed’ your ‘confidence in climate science’,because you had little anyway.

      • Nick,
        I have no idea what Oliver’s level of confidence in climate science was prior to the “hide the decline” revelation, but I can say that I was a reasonably firm believer in “the consensus” up until I began paying attention (around 2006) to the ongoing battle McIntyre was having with the Realclimate group over the hockey stick. By 2007, having seen the unbelievable disingenuousness of these key defenders of the hockey stick, I was becoming truly sceptical. Sceptical not so much in the sense that I discounted the potential for GHGs to cause serious warming, but sceptical in that I felt I should place zero faith in anything a hockey stick defender had to say, regardless of their credentials. I know that the folk associated with Realclimate have probably done much worthwhile work, but I was also certain that they would spin and obfuscate shamelessly to defend shoddy work.

        By 2009, when the climate gate emails were leaked, with their “hide the decline” revelation being just one among many, for me it was just confirmation of behaviour long suspected from following the hockey stick wars. However, it should be remembered that climategate drew the attention of many people to the fact that there were serious sceptics for the first time, and that there was also some very dubious conduct on the part of mainstream, IPCC sanctioned climate scientists. I suspect that the pathetic excuses being put forward to explain the why “hide the decline” isn’t really as bad as it appears, are right now playing the same role in converting a new wave of neo-sceptics that the hockey stick wars played for me.

        So I wouldn’t be so dismissive of the power of the ongoing, absurd excuses being offered to explain away “hide the decline” to convert a new generation of unbelievers.

      • Jim,
        Entirely agree, I was a staunch AGW believer right up until sometime 2008 – and (other than not doing any research to get a deeper level of knowledge) I still cant understand why! In talking to family and friends, the only reason they seem have a pro-AGW slant is because they (like me) hadn’t followed anything other than media reports on the matter.
        ‘Hide the decline’ is as damning as the Team’s continuing inability to play ball with the rest of civilised science.

      • I also have to agree with Jim West. My firm ‘belief’ in AGW had already been undermined by some extremely bad papers about mosquitoes, arthropod borne disease, and the effect a warmer Earth on wildlife (I am a biologist). But, I assumed these were just opportunists jumping on the gravy train and that the problem was with the journal review process, not AGW.

        But the Climategate emails made it all too clear that there was no science at all in all these famous papers in Nature and other ‘prestige’ journals. Rather, all the sound and fury appeared to be generated by an unscrupulous cabal eager for grant money, fame, and lots of CO2 generating trips to warm and pleasant spots where they could regurgitate their story to a corrupted press and conniving politicians.

        As far as I can tell now, many of the assumptions of AGW appear to be false, nothing that one reads on climate change from Nature to Drudge is reliable, and no one has a clue what is happening with the Climate.

      • Exactly, well put!!!

      • Late reply…
        Dave, your last paragraph is where we all should be at this point.

        Some laugh at skeptics as “deniers” about CO2 and GHGs. But their ridicule should be turned right around and aimed at the supposed science as it has been presented. With them using tricks and hiding declines, just HOW are any of us to know anything for real whether there even IS warming? Too many stations show flat or declining trend lines in the raw data – even ones that have large increases in the adjusted data.

        What was done by the hockey stick team in hiding the decline – is there any reason we should accept their other graphs and conclusions, when they might just as readily “hidden” other declines – and in the case of the MWP, e.g. – hidden INclines, as well.

        In other words, if we can’t believe them – Muller won’t believe anything they write or wrote – how do we know anything about climate? And as everyone is coming to ask, “If tree rings diverge now, of what use are they as proxies, and if tree rings aren’t included, what does that leave us as to believing the temperature reconstructions tell us anything at all?”

        We may be back almost to ground zero.

      • Well it sure destroyed mine! I am not a climatologist, and I had just assumed that the evidence for AGW was conclusive. I downloaded the emails out of curiosity….. and I was totally gobsmacked!

        I was then doubly gobsmacked (if that is possible) when people started to claim that nothing was wrong – that the Nature trick was only a trick in the sense of something clever. How amazing is it, that to the best of my knowledge Nature has never corrected that paper, and yet the trick has been exposed by the Daily Mail!

        http://www.dailymail.co.uk/news/article-1235395/SPECIAL-INVESTIGATION-Climate-change-emails-row-deepens–Russians-admit-DID-send-them.html

        Something has to have gone badly wrong when the Daily Mail corrects Nature on a science story!

      • Jim;
        My timeline is very close to yours. And the stench of disingenuousness had about the same effect.

        The hiders and excusers are skeptics’ best recruiters.

    • Oliver Manuel: “But the pawns involved are not to blame. The responsibility lies much closer to the top of the research food chain.”

      You are to gracious. The pawns have plenty of motivation in the form of taxpayer funding, ensuring their continued employment, more research equipment, and computing power. Thus the pawns are just as responsible.

      Take away the pawns funding and we soon see who the dedicated scientists are and those scientists who actually believe GW is real; since the rest of the pawns will leave in droves for greener $$$.

      U.S. Congress should defund all Climate work at NASA, since it interferes with their primary job, and is duplication of NOAA.

      • I agree, Darren.

        But the pawns, including Gavin Schmidt (below), are not at fault.

        But the problem has been growing – out of public view – for several decades, probably in annual budget negotiations for federal research agencies at the top of the research food chain.

        E.g., between the President of the US National Academy of Sciences and the Chair of Appropriations for Science and Technology in the US House of Representatives.

        With kind regards,
        Oliver K. Manuel
        Former NASA Principal
        Investigator for Apollo

      • As a former NASA PI for Apollo samples, I requested answers in 2008 (before secret efforts to “hide the decline” became public) to the following questions, orally and in writing, at a gathering in the NAS building that included the President of the National Academy of Sciences and the then-Chair of Appropriations for Science and Technology in the US House of Representatives:

        Why did UN’s Intergovernmental Panel on Climate Change (IPCC) – and US federal research agencies like NASA, DOE, NOAA, NSF, etc. – work together to promote this web of mis-information:

        1. CO2 from the tail pipes of Western economic engines caused global warming.

        2. Earth’s climate is immune from the cyclic changes in sunspots and solar activity.

        3. Hydrogen fusion in the Sun bathes planet Earth in a steady and unchanging flow of heat.

        4. Solar neutrinos from Hydrogen-fusion in the Sun oscillate away before reaching our detectors.

        I do not understand the motives for these actions, but therein is the key to the debate over anthropologic global warming and the havoc it has wrecked on our economy.

      • These questions are still unanswered.

      • Oliver K Manuel is right – there are no poor soldiers only poor generals.
        The problem is simple – as is the solution. When, in 1993, the IPCC first wrote the forerunner of the “Principles Governing IPCC Work”, the very first words were:

        “The role of the IPCC is to assess on a comprehensive, objective, open and transparent basis the scientific .. .. etc.”

        The key words are open and transparent. The IPCC also stated:

        “Conclusions drawn by IPCC Working Groups or task forces are not official IPCC views until they have been discussed and accepted by the IPCC Plenary.”

        This is saying clearly that it the government members of the IPCC that call the shots. However, no one can seriously suggest that any previous assessment by the scientists that undertook them has been open and transparent. We only know anything about the last, AR4, because Steve McIntyre filed an FoIA request for the Government and Expert Reviewers Comments. We then learnt a lot more from some brave individual that released the UEA emails.
        So with all that has happened is AR5 going to open and transparent? Not if the scientists get their way. This is the instruction on the AR5 WGI website:

        “It is the IPCC practice that all drafts are confidential and should not be cited, quoted or distributed. This principle, which must be adhered to, is clearly stated when report drafts are sent out for expert and government review and also applies to the review comments and author team responses. However, upon completion of the Report, the review comments and responses are made publicly available and are retained in an open archive.”

        It is not the IPCC practice. It is the practice of the ad hoc volunteer scientists in the working groups who are supposed to work to the IPPC Principles. What in effect they are saying is the paying public can make all the fuss they want once the Summary for Policymakers has had the “media blitz”, which one IPCC Bureau member urged the InterAcademy Council to call for on page 102 of its public Comments.

        Not only is it not the IPCC practice, IMHO it is no longer lawful for any public authority in the European Union refuse to disclose these to anyone in the world unless they can show that it is in the public interest that these completed documents, which have been distributed to hundreds of other people should be withheld from the paying public until after the “media blitz”.

        I have asked the British Minister of State for an undertaking that the first AR5 WGI draft scheduled for delivery to government “focal points” on 16 December 2011 will either be published by our Department for Energy and Climate Change immediately or made available to any one that requests it.

        Government “focal points” are also entitled to have a copy of all Expert Review comments and I have asked for the same undertaking for those on the first draft which should be consolidated by 16 April 2012.

        Such is the Internet oversight of climate science today that the certainty that any liberties taken by the scientists will be very publicly ventilated. We might then expect a more balanced Assessment Report in which the controversies are properly recorded.

        What Rep. Blaine Luetkemeyer should have put into his amendment was to cut off funds to the IPCC unless it fully enforces its Principles and Procedures – specifically publishing drafts and comments when complete, and web casting all IPCC and Working Group formal meetings. Who could argue against that?

      • David Holland,

        Your conclusion is absolutely spot on. I wonder, however, if the IPCC is capable of such openness in its current form? Perhaps if the entire executive of the IPCC were replaced then your hopes could be realised….it’s certainly an intriguing idea.

      • I think if enough of you in the USA lean hard enough on your political representatives you might persuade the US government to insist that the IPCC rules of openness and transparency are followed as well the IPCC rule that Expert Reviewers should have access to any data not available in the published papers that are cited by the Lead Authors.

        Making payment of your IPCC dues conditional on the scientists following the rules might even get through the Senate where just stopping the funding may well not.

      • Sorry David, you’re barking up the wrong tree with me. I’m an Aussie, writing from Brisbane! Believe me, we have problems of our own, with our current government now proposing a carbon tax that they think will persuade the rest of the world to do the same.

        Oh dear.

      • I really have a problem with the analogy that paints scientists, who pride themselves as, and really should be the most imaginative and against-the-grain thinkers the world has…. as petty soldiers who simply do the bidding of generals.

        Soldier != Scientist
        Scientist != Soldier

        It will always be so.

    • From a UK perspective, the public credibility of climate science has not declined very much (about 75% of people surveyed by the BBC shortly afterwards thought climate change was a reality) BUT the effect of “climategate” as a whole has been an increase in the number of people who feel the worry is exagerated and those who had little faith in the science before have become more resolute. There has been a sense that the scientists involved were naive and inarticulate in choosing misleading words, but not currupt. This seems a typically British approach to understanding senior decision makers (those “closer to the top of the food chain” are too befuddled and disorganised to be currupt), and very different from the views expressed here about the divided opinions amongst US citizens, which is interesting for me to grasp.

      http://mitigatingapathy.blogspot.com/

      • I wouldn’t trust anything that comes from the BBC regarding this issue. They have an agenda and a history of bias.

        Prior to Climategate there were very few skeptical articles in the media. This has now changed significantly. Skeptical comments at sites that support the ideology (such as the Guardian) have also increased markedly.

        Since the release of the e-mails, I have met many, many people who have changed their point of view. Whether Climategate is the most valid reason to become a skeptic is another matter altogether.

      • I don’t think the BBC has a history of bias and their agenda is one of working out what equal representation might mean. The survey was commisioned by the BBC, but undertaken by an independent organisation, with over 1000 interviews. Unless you are suggesting a conspiracy, the survey seems reliable AND a reflection of the people I meet at Football or down the pub.
        As for The Guardian, there is a problem with so called Astroturfing and, more intriguing, US citizens make up a large chunk of the “skeptical” posters (based on spelling, language differences, cultural references, saying “as an American..”) which reinforces the sense that it is a coordinated campaign.
        I have no axe to grind on the matter – if 75% had said climate change is a myth, my department would probably get more money to communicate its findings better!

        http://mitigatingapathy.blogspot.com/

  2. It’s good to see someone with a bit more credibility (i.e. yourself) taking a line on this issue- it’s something that’s bothered myself and others for a while; the ‘divergance’ and the sensitivity of the proxies to short/medium term temperature fluctuations (in fact the recent divergence if anything suggests a marked INsensitivity).

    Personally i also refute the linguistic explanation surrounding the ‘hide the decline’ and ‘trick’. I’ve never used such terminology in my career as it is open to mis-interpretation and can be seen as unprofessional.

    I’d have had far more respect for them if they’d just said that they were just having the equivalent of an off-line chat and had bodged the terminology, rather than try to defend it and pass it off as common scientific parlance.

    • Labmunkey:

      “I’d have had far more respect for them if they’d just said that they were just having the equivalent of an off-line chat and had bodged the terminology, rather than try to defend it and pass it off as common scientific parlance.”

      I think the problem they face now is that any admission of that kind would destroy their careers and, quite possibly, result in criminal prosecution. Remember, there has already been huge amounts of taxpayer money spent on various desperate “low – emission” schemes in the name of the hockey stick graph.

      • quite- and they’re far beyond the point of no return for such an action- they just should have taken this line from the start!

  3. You know it’s past your bed time when you spell your own handle wrong. Sigh.

  4. An excellent and some what surprisingly frank analysis/discussion of the `hide the decline’ issue. It is really not that hard to get your head around. It amazes me the lengths that various scientists have been gone through to deflect attention from this issue.

    Anyone with the most basic scientific training should recognize the problem. That the IPCC report should have failed to recognize the problem (the hide the decline issue, but more importantly the implications for paleo-temperature reconstructions) is sufficient to raise doubts in the scientific impartiality of the IPCC reports. If this is susposed to be the gold standard, then heaven (or hell) help us scientists.
    With respect to Mann, Briffa, Jones et al. and all the other scientists that defended the original study and the hide the decline issue, as a geologist it strongly calls into question their impartiality as scientists. This then reflects on all of their other published work, and indeed the organizations that they work for (also the many researchers that work in their shadows).

    If a scientists breaks the very thin ice of impartiality then it irreparably fractures their standing in a proper functioning scientific community. That this hasn’t happened in the climate science community is perhaps the most cause for concern

    Philip Finck
    Nova Scotia Department of Natural Resources

    • If a scientists breaks the very thin ice of impartiality then it irreparably fractures their standing in a proper functioning scientific community. That this hasn’t happened in the climate science community is perhaps the most cause for concern

      Exactly. If this hasn’t happened, is climate science a properly functioning scientific community? The answer has to be no.

      I’m glad Dr Curry has just deleted the worst of the personal attacks that defaced this thread. But they were interesting in this respect: this is exactly the kind of abuse directed at anyone questioning any aspect of IPCC-anointed climate science on the blogosphere for many, many years. Having seen Dr Curry’s concern for truth and honest debate on all aspects of the science so far, to see her attacked in this way on hide the decline is extremely revealing. The corruption spreads from the centre and the infection of the blog attack dogs is something rotten.

      Climate science proved itself corrupt in its reaction to McIntyre to McKitrick from 2003. In Dr Curry’s words in Feburary 2011 we have the one champion of true science making herself visible from within the camp. Such courage will transform the scene beyond recognition – in time. What happens in the meantime, God only knows!

  5. Sorry, I am with Muller. Many low frequency reconstructions calibrated to temperature by the original authors should have been included, but were not. Some of the newer papers tossing a thousand plus reconstructions together without proper evaluation of the individual reconstructions are psuedo-science. One should know the limits of one’s meta data!

    • There are multiple issues, not just a choice of how to present a graph:
      1.Subjective choice of trees/sites for sampling
      2.Post-hoc dropping of “non-responders”
      3.Linear response to temp assumption (which is actually known to be false.) which makes the inverse problem undefined.
      4.Ignoring six sigma outliers like Yamal larch which heavily affect the result
      5.Hiding adverse verification statistics (R-sq of 0.05 means you have nada)
      6.Unjustified weighting (bristlecones 400x others)
      7.Proxies different orientations (+ vs – temp indicator) in different time periods of the recon.
      8.Choosing graph baseline to emphasize post-1980 “warm”
      9.End point padding—even worse with instrumental data
      10.Hiding the decline as discussed above
      11.Thick red line for instrumental data to make it look “hot” and to hide lines underneath that are going down.
      12.Repeated use of “robust”, “similar”, “reliable” with no quantification.

  6. You have gone significantly over the line with this post. Accusations of dishonesty are way beyond a difference of opinion on how a graph should be displayed.

    If you thought that a single, smoothed graph of estimates of paleo-temperature told the whole story of paleo-climate reconstructions is far more a failing at your end than it is the authors involved. How can a single graph say everything that can possibly be said?

    Summary graphs are by their very nature, summaries. The graphs you pick out were summaries of various estimates of what paleo-temperature estimates from the literature were. It is therefore not surprising that they show only the reconstructions where the authors had confidence that the reconstructions were actually of the temperatures.

    Problems with modern divergence – which only applies to the Briffa et al curve in any case – are issues to be dealt with in the technical literature, as they still are.

    The quote from the emails on the ‘dilution of the message’ was related to a completely different issue – the fact that Briffa et al’s initial reconstruction did not have very much centennial variability at all (the version of the graph that was being discussed is here: http://climateaudit.files.wordpress.com/2009/12/ipcc_tar_zero.png ). You are being misled if you think that is related.

    One can have a difference of opinion in how to present a graph, and that depends entirely on what point you want to make. If you want to make a point about multi-decadal temperature changes in the past, it makes sense to include estimates of those temperatures and the uncertainties. It doesn’t make much sense to include annual estimates, or seasonal estimates, or parts of the curve that the originators think doesn’t reflect actual temperatures (for whatever reason). The only issue is to ensure that the graph is sufficiently documented so that these choices are clear (which in the WMO report they were not sufficiently so, but were fine in the IPCC graphs).

    But to ascribe a difference of opinion to dishonesty is to remove yourself from any sensible discussion on the topic. Perhaps if I was to find a graph in one of your papers which I thought didn’t show some aspect of the data I was interested in, and then accuse you of dishonesty? Would you react well to that? This is exactly the same.

    How can you claim to be building bridges, when you are so busy burning them?

    • Gavin, the field does not need any more summary graphs of this nature. They have done an enormous disservice to climate science and its credibility. Continuing to defend these kinds of graphs is beyond anything I can understand. Leaving out that data and putting a “likely” confidence level on conclusions from that data is bad science, anyway you slice it. If you don’t like dishonest, try misguided and pseudoscience. There is no way this is defensible scientific practice. I really hope we don’t see any more of these kinds of graphs, in the AR5 or elsewhere. I’ve tiptoed around this one long enough, I’m calling it like I see it.

      • Well done Judith.

        It is unbelievable to read Gavin trying to defend the indefensible (you shall not hide data) by his usual method of obfuscation and misdirection.

      • John F. Pittman

        Dr. Curry, there is more here than is noted in your post. Not to make your eyes glaze over, but in order to avoid a circular argument wrt models, the lack of a long term temperature data set where an average temperature could be reasonable computed, the paleo work is a necessity for attribution. Without attribution the whole IPCC meme of its Bayesian attribution, cannot be supported at the levels quoted.

        You state : ” I am personally having a difficult time in seeing how this stuff has any credibility at the level of “likely” confidence levels reported in the TAR and AR4.” But within the framework of the IPCC this would extend it in to the area of attribution.

        While I agree with some of what Gavin stated, in terms of loss of confidence, the climategate emails are worse in context. It is not as Gavin states a simple disagreement of a graphical presentation. That is but one issue and as you have noted, there is much disinformation around. Nor is Gavin’s comment that: ” Problems with modern divergence – which only applies to the Briffa et al curve in any case – are issues to be dealt with in the technical literature, as they still are. ” a good summary of the issue of the noted problems with the different reconstructions. But I would note the tense that Gavin used is the same that Dr. Briffa used, and that is that these are issues, as in unresolved issues.

        That is why I disagree with Gavin about you stepping over some imaginary line. The real problem is that a line was stepped over. It was the line of trust. This does not mean that when the answers are known, that Briffa et al, will have to be right or wrong, it does mean the “on message” write-up of attribution has problems.

      • “I’m calling it like I see it”
        How brave of you.

        My point is that by lowering yourself to insult, you block off all sensible discussion of specific technical points – if you are so certain in your thinking that no further discussion is required, then fine. No more discussion will occur. But it would have been far better for you to have had the character to allow for disagreements without being disagreeable (did you not pick up anything in Lisbon?).

        For a useful analogy, let’s take a different figure, say, figure 4 from Webster et al (2005):
        http://www.sciencemag.org/content/309/5742/1844/F4.large.jpg

        This shows a big increase in cat 4+5 hurricanes from 1970 to 2000. But why is it cut off at 1970? Surely it can’t be because the data is poorer prior to that? No, it must be that the pre-1970 data doesn’t support the thesis of the authors, they must be hiding the decline! I insist that the ‘adverse data’ be shown on all graphs, and that anything else is highly misleading. And without any further thought, it must be dishonest – because how is it possible that anyone could have an opinion on how to display data that differs from mine without being dishonest? Pseudo-science!

        You see how easy this kind of stupidity is? What is point?

      • Good one Gavin, brilliant argument.

      • I’ll let others judge. But your method of argument in the top post and the conclusions you draw can be argued and drawn for any subjective decision about pretty much any presentation of complex data. Once you do it based on your prior prejudices against one set of researchers, the flood gates are open to apply it to anyone. We therefore end up with a situation where any difference of opinion is put down to dishonesty, and the process of objective scientific analysis has been tossed to the wolves.

        You see your stance as brave, while in fact it is just lazy. I’m sure your students are proud.

      • Brilliant defense. Anyways, I’ll take lazy and prejudiced over dishonest, if you insist.

      • Gavin’s got an excellent point here.
        Along with the Y2K “error” found that impacted global temperatures by what – nothing?, this issue is one that has been elevated in blog discussions WAAAY out of perspective.
        Judy, what you are doing is disingenuous. As a Ga Tech grad in EAS, I’m embarrassed.

      • Jen, are you saying that hiding the decline is an appropriate or justifiable practice? Are you saying that the incessant defence of that practice lends credibility to the field or those working in it? If so, then I agree with you that you should be embarrassed and implore you to return your degree at the earliest opportunity.

      • Most of the people who are outraged about hiding the decline have misunderstood, what was done. They think that we have evidence of declining temperatures and that this evidence is hidden. They do not understand that the problem is in what the issue does for the credibility of paleoclimatic temperature records, not in what we now about the temperatures of the hidden period. The correct interpretation would never have lead to the furore.

        The decision is foolish in afterthought and the explanation given by those who made the decision seems to indicate that it was also made for wrong reasons. When the paleo data contains features that speak against its reliability, the right choice is not to hide them, but to show them and explain why they are not so serious. If that cannot be done – then they are so serious.

        How stupid the decision was should by now be evident to everyone. Arguing against that observation only worsens the situation. From the point of view of science, we need better easily accessible analysis of the paleo data than we have now available. The doubts on the reliability of the paleo temperature series are wide spread also within the main stream climate science community. Many in this community appear to think that the situation is worse than it would be without any of this data. Some of the best known climatologists here in Finland have hinted in this direction also in public.

        It is also true that the two best known groups in Finland that produce raw data for paleoclimatic analysis disagree with the conclusions of the temperature reconstructions. They are not statisticians, but it tells also about the problems. One of the groups has analyzed tree rings in Lapland and the other lake sediments.

      • “They think that we have evidence of declining temperatures and that this evidence is hidden.”

        Who around here do you think still thinks that, or has ever thought that?

      • Well said, Pekka.

      • It is completely obvious that that is the most common interpretation outside the community that follows matters in detail. Look at this quote from Judith’s post

        “4 February 2011, Investor’s Business Daily: The ClimateGate scandal was a direct result of scientists — and we use the term loosely — at Britain’s Climate Research Unit and others, such as Michael Mann, conspiring to manipulate data to “hide the decline” in global temperatures.”

        It is clearly about hiding the decline in temperature, not in a proxy time series. The same is true everywhere.

      • Pekka,

        Nobody here thinks that, at least, not that I’ve seen.
        Perhaps some journalists etc do, but since when did they count?
        It seems to me that it’s become yet another strawman – you misunderstand ‘hide the decline’, ergo you know nothing – end of discussion.

      • Peter,
        I tried to tell it clearly that I am not making that statement on the readers of this blog. “Some journalists” is a much better proxy for the wider audience, which is still interested enough to form an opinion.

      • Pekka,

        What does it matter what some journalists think, write or say? They generally get most other things wrong anyway.

      • Pekka, at this point I think the landscape has changed somewhat. Now the landscape seems dominated by those that fully understand the implications of the “hide the decline” “trick” and those that don’t give a rat’s.

        There does seem to be a persistence of low-grade enviro-journalists, some of whom still trot out the “declining temperatures” assertion, but I think that this is more indicative of a much broader problem with the standards in journalism today and the guff that exists between the environmental journalists’ scientific understanding and the motives of the scientists/pseudo-scientists they either hero-worship or (cripplingly uncritically) pen-push press releases on their behalf.

        It is worth checking the comments sections on news pieces where this miscommunication occurs, to see if the misunderstanding is corrected there by subscribers/regulars. In my anecdotal experience, this invariably happens.

        It may not always – obviously I cannot say for sure – but I find that in general there is a far greater level of scientific understanding among the public than among the journalists. This is markedly the case at the Guardian, where the leanings of news pieces are diametrically opposed to the dominant views expressed in the comments.

      • From http://wattsupwiththat.com/2011/02/19/fred-singer-on-the-best-project/

        “However, the most serious revelation from the e-mails is that they tried to “hide the decline” in temperatures, using various “tricks” in order to keep alive a myth of rising temperatures in support of the dogma of anthropogenic global warming”

        Although several people pointed out that this was wrong, it has not been corrected.

      • @louise

        I am baffled as to why most of your contributions here are complaints about remarks on another blog entirely. Why do you not post about them over there?

        PS – I have seen pictures of both Anthony and Judith. They are not the same person.

      • Is Fred Singer a “low-grade enviro-journalist” and if so, why is he guest posting at WUWT?

        If he’s not a “low-grade enviro-journalists” then this comment of his shows that this particular interpretation of “hide the decline” is still spouted as if it’s true and whips up a storm (as intended).

      • Might misleading be a better term?

      • Judith Curry.

        You obviously disagree with the recontruction, or you would not have started this thread.

        Can you post data describing a trajectory that you believe represents the warming in the last one thousand years, as you accept it?

      • That’s not really the point of the thread (though i understand your question).

        Splicing and omitting data is not sound practice- hence the ‘discussions’.

      • Can you post data describing a trajectory that you believe represents the warming in the last one thousand years, as you accept it?

        Because handwaving and just plotting a curve with metaphysical insights as Judith “accepts it” is just so much better than faulty statistical methods that retrieve bad proxy data, innit?

        I just don’t get this point. I get this kind of comment everytime. “If you don’t think that it is X, then tell me what it is”. Well, you know, sometimes if we want to be rigorous and scientific, we have to answer “I DON’T KNOW”. But this is perhaps too honest and so little useful politically… I mean, it’s so much more exciting to say that we do know what’s going on and it’s the white man’s fault (or Rush Limbaugh, or Osama, etc.)

      • “I’ll take lazy and prejudiced over dishonest, if you insist.”

        Well, apprently, there’s no need to choose.

      • Touche, the first clever comeback that I’ve spotted :)

      • Judith
        Its great that you have lured Gavin out to play. Freedom to debate is not something he offers dissenters at RealClimate. Why is that Gavin?
        Ed

      • There are lots of dissenters at RealClimate.

        Why write such an easily disproved notion?

      • Jeffrey – Name one. Just one – and post an example here of a dissenting question that was asked.

      • Roger Pielke Jr. comments there all the time.

        Linking to individual comments isn’t possible, but there’s a search box on the 1st page. Happy hunting.

      • Jeffrey –
        Bull puckey. RPJ “may” comment there sometimes, but I also know there are times when he’s been moderated too. Why?

        Linking to individual comments isn’t possible, but there’s a search box on the 1st page. Happy hunting.

        So you have no answer and you’re too lazy to go look for one. Others manage to link to RC comments – what’s your problem?

        This is how you do it – I picked a thread and a comment within that thread at random –

        http://www.realclimate.org/index.php/archives/2011/02/ee-threatens-a-libel-suit/

        http://www.realclimate.org/?comments_popup=6956#comment-201415

        If you’re gonna lie to me, then learn how to do it better.

      • Gavin is trying to make this out as a judgment call about the presentation of complex data. But that is a distraction from the really incriminating evidence. Phil Jones wrote that he completed the task of attempting to “hide” the decline. The word hide indicates a deceptive intent, not a judgment call about the quality of the data. It appears that almost the entire climate (so called)science community has defended this data hider and he has been reinstated to his position as head of a major climate science research institution. The lack of outrage by the climate science community at his reappointment destroys the credibility of nearly all research produced by the climate science community. Once caught hiding or defending hiding, the climate science community can never be trusted. It doesn’t matter how many proxy studies back up Mike Mann’s hockey stick, we have no reason to believe they were not also hiding important data.

      • I reread Gavin’s response three times. All I can say is “Huh? What?” AS
        As a Georgia Tech graduate in Mathematics, I am happy to see that
        the call them as I see them attitude I remember still exists two
        decades later.

        Also I am reminded that the party who sounds angriest is the
        one who is losing the argument.

      • Sadly you stoop to character assasination instead of reasonable discussion. After seeing a little of what goes on at The Open Mind, RC, and others I for one am not surprised.

        What this shows to most of us is that you do not have a defense of the scurrilous activities that have been occuring. You can only continue to try and circle the burning wagons.

      • Bravo Gavin,
        Controlling the message to the bitter end. You are a gallant and loyal soldier to the cause. Faced with overwhelming odds, even gallant soldiers clips run out and their positions are overrun.
        Mann 98 is indefensible.

      • Was it Patton who once said, “Right or wrong, my country”

      • Steven Decatur, arount 1818

      • Gavin,

        Had the hurricane graph to which you refer contained earlier proxy data to reconstruct the period prior to 1970 and then used the post 1970 actual hurricane data spliced on the end to hide a divergence with the proxy data, would you be OK with that? Would you consider that to be misleading, especially if it wasn’t made crystal clear what was being done?

        You’re a fine scientist Gavin – but I suggest you might want to leave the political chicanery to others rather than call your own judgement into question in this manner.

      • Craig Goodrich

        As to strictly technical points, Gavin, about that subdirectory in the raw MBH98 data labeled “CENSORED” that held proxy data directly contradicting the MBH conclusion and was excluded from the paper …

      • You appear to be so wedded to the defence of an indefensible cut/splice/smooth that you perceive even wholly warranted criticism of the practice and its delivery as a personal sleight.

        Oh well.

      • I’m sorry, Gavin, I missed that. Did you say that cutting, splicing and smoothing tree ring proxy data with the instrumental record in order to “hide the decline” in tree ring proxy temperatures and a decline in the correlation between the two is.. good, honest, scientific practice? Or.. not?

      • Gavin said: “This shows a big increase in cat 4+5 hurricanes from 1970 to 2000. But why is it cut off at 1970? Surely it can’t be because the data is poorer prior to that? No, it must be that the pre-1970 data doesn’t support the thesis of the authors, they must be hiding the decline! ”

        – I think most folks here agree on this point, as we agree the decline should not have been ‘hidden’. Does that mean you, Gavin, are in agreement now?

      • Actually, since Gavin is a NASA guy, I would have figured he knew how long satellites have been making measurements in the infrared. Maybe not. Therefore, the decline was not hidden.

      • From what I’ve seen, Gavin is not a master of the term “analogy.”

      • Oh quite to the contrary. I watched the entire IQ2 debate where Gavin went on and on with his analogy about climate scientists being CSI investigators to an highly intelligent audience that paid over $50 a ticket to watch and judge an intellectual debate. He was then shocked when he lost the debate after disrespecting the intelligence of his audience with his childish run on analogy. Gavin understands analogy perfectly he just doesn’t know how to use it and when.

      • Judy –
        Gavin actually asked a good question – sorta. There is intermittent satellite data back to 1964. Although it might not be considered useful for publication purposes.

      • Hurricane experts have been fairly emphatic about when the satellite data were sufficiently reliable to analyze hurricane intensity. We chose 1970, but apparently the methods of actually analyzing hurricane intensity were not consistent or adequate in some regions of the globe until 1980. So the criticism of our data set was using some data and analyses that were no good (no one criticized us for not attempting to go back into the 1960’s). Not exactly an analogous situation to the tree rings.

      • That assessment is correct Judy. The analogy to the tree rings is bogus. 1970 is also the first really complete year that the North Eastern Pacific has data. If the study were updated (hint hint) through 2010, a starting point of 1980 would have at least three decades worth of data, sufficient to examine some aspects of short term climate.

        However, Judy criticized Klotzbach (2006) back then for not using enough data — but praised Elsner et al. (2008). I would describe Judy’s position on length of tropical cyclones records as “evolving”. Yet, she readily admits the uncertainties and does not hide the declines.

      • Judy – I didn’t mean to criticize. I “was” curious, though since I know there was “some” data in the 60’s.

      • Dr. Schmidt,
        You are really the last person in the blogosphere to lecture anyone about lowering themselves to insult.
        The real question is why are you doing this to yourself?

      • There is a treatment for cataracts practiced in the third world. A doctor comes into a village and treats everyone that suffers from cataracts. A thorn is used to pierce the lens of the afflicted, the cloudiness drains, and sight is restored. The doctor collects his fee and leaves town.

        Now we might graph this over time and obtain some insight into the treatment. It is quick, inexpensive and delivers results quickly. We might also splice onto the end of this graph the results of conventional first world cataract surgery, which will show that the trend continues and sight is restored.

        However, the third world treatment has a result not shown on the graph. After the doctor leaves town, those treated begin to lose their sight until they are completely blind. Since we don’t really know why this is we left it off the graph, because it doesn’t fit the rest of the data.

        After all it is simply a matter of opinion that we should have shown the decline in sight on the graph. We did make note of it in the detailed notes in the original case study.

        Now perhaps you feel the cases are different. One deals with cataracts, the other with temperatures. And since the result of the first is blindness in 100% of those treated, we should have made the problem more obvious.

        After all, in the temperature record, it isn’t like we are talking about a complete overhaul of the industrial and economic base of our economy and hundreds of trillions of dollars in global taxes administered by the UN. What possible harm could come from that?

      • Gavin, the graph you claim as an analog does not involve the pre-1970 period, whereas the “hide the decline” graph in question does involve the post 1960 period. The graphs are not analogous.

      • Exactly. There is no analogy in Gavin’s “analogy”. The “hide the decline” graphmakers were leaving off (inconvenient) data that exists in the timeline they were graphing. The hurricane example above doesn’t leave off any data in its timeline. Score one for JPeden.

      • Correct me if i’m wrong but your analogy doesn’t hold- on one hand, ‘temperature’ data that didn’t fit the official line was left off a graph, on the other it’s just a scaling issue.

        I understand the degree of interpretation required in these sorts of studies is an unavoidable by product, but if this had to be done then surely a different data set should have been used to avoid precisely this sort of conversation?

        Or am i missing the poin.

      • This is not a good analogy, in the case of paleo proxy, the fact that they diverge for recent temperature cast doubt on their validity, because they diverge from the most accurate record we have (the recent one).
        In the case you mention, the “hiding” occur at earlier date, where the records are poorer. It means that the curve is not as long as what we could wish, showing only a very short time and thus maybe insuficient for drawing any info about evolution of frequency of strong hurricanes. It does not transform the confidence we have in the actual huricane frequency shown though.

        But as you, I see a that a line has been crossed. The line is between doing science for increasing knowledge, and doing science for pushing a theory/worldview/agenda/policy (your choice).
        The line between the two is not always clear, but in this case, I think that Judith has shown to be on the former side, and you (together with the IPCC and the Team) have shown to be on the later side.

        This is not immoral to be on the second side.
        But there, you do not benefit from the reputation of total objectivity that science usually enjoy. You will have to demonstrate objectivity and robustness and defend it, they will not be granted for free….And imho, tree ring proxies for reconstructing global average temperature do not pass the robustness test.

      • The problem with your pathetic analogy is that it is fairly easy to argue that we didn’t have comprehensive or acurate records in the past (such as cyclones pre-1970). However the actual case being discussed is that the modern tree ring proxies, taken with the utmost scientific care, show behavior that does not correspond to the temperature record. So it is the utmost level of scientific malfeasance to attempt to characterise their prior behavior as reliable in any way.

        Another sad truth about your “argument” is that fact that rebuttals pointing out the immense flaws in your argument would have been deleted at FauxClimate by your team of anti-science moderators.

      • “My point is that by lowering yourself to insult, you block off all sensible discussion of specific technical points – if you are so certain in your thinking that no further discussion is required, then fine. ”

        Speaking of the devil, what are you doing in RealClimate then? You are deleting or moving every critical technical points to the borehole. You are allowing only those comments in, where you think you have a good answer to, or which pleases you. That is not discussion, that is propaganda.

        At least Judith is letting your comments in, but as far as I can see, you already have deleted Judy’s comment from RealClimate.

        Thats hypocrite and arrogant, IMO.

      • Oops, this particular comment was actually not deleted. I was looking on a wrong thread. Apologies.

        But still, there are plenty of other examples. Why delete critical technical points from RC?

      • Mr. Gavin,

        You might have a valid point with your “For a useful analogy, “; except you propose it as if those claiming Global Warming have never been found manipulating charts’ appearances to hide those – all so inconvenient truths.

        If you want to have an honest and meaningful discussion and debate on Global Warming vs. playing a pseudo victim card with your analogy; then start calling out those who have been manipulating the weather station temperature data (NCDC/NOAA) being used by the pro-pundits of Global WArming to claim increasing global temperatures over time.
        Please don’t feign the data hasn’t been manipulated, since it is obvious that the number of Weather Stations was reduced over time by not entering monthly data for specific stations, with a preference to reducing stations in colder locations. Unless of course you feel it is valid to compare bushels of Apples to baskets of Oranges to branches of Bananas to sacks of grapes to handfuls of nuts; then draw a conclusion on which one tastes better.

        While you are at it, how about calling out those who keep morphing the entire GW debate (as in Global Warming, Global Climate Change, Global Climate Disruption, Global Climate Challenge) in unprofessional / unscientific attempts to head-off any counter arguments? Or do you approve of the tactic of using a “moving target” to prevent/derail discussions and debate?

        Same goes for the SPIN on Global Warming being solely caused by man-made CO2 to man-made CO2 being a contributing factor to CO2 being only an initiator to whatever the latest CO2 claim is. All of the aforementioned SPIN being done to cover-up the fact pro-pundits of Global Warming ran into cold-hard science, physics, and observable facts that ran counter to or conflicted with their previous claim on man-made CO2’s effect as a Green house gas.

        BTW: Any chance you ask Al Gore to come help shovel some of that white flaky Global Warming… ;)

      • For readers who have never had the pleasure of “debating” a Politically Correct interlocutor, please save this series of posts from the infamous Dr Schmidt.

        His clever verbal ripostes are straight out of the PC manual, from the entry: “Exposure of midconduct, how to respond.”

        In a nutshell, the standard PC rsponse when misconduct is exposed is:

        Admit Nothing. Deny Everything. Make Counter-accusations.

        The counter-accusations should be personal. The more personal and scurrilious the better. Attack motivations. Attack personalities. Attack, attack, attack. Use the “in crowd” to exclude critics. Sneer.

        This short manual of PC tactics should help as you encounter more of their ilk.

        For a clearer view of these tactics, if you can stomach it, visit their own websites.

      • For those following along at home, the linked graph is from this paper …
        http://www.sciencemag.org/content/309/5742/1844.full?sid=8e9aed61-22ae-48f4-a66c-fffb9d012793

        … which includes the following words:
        We deliberately limited this study to the satellite era because of the known biases before this period (28), which means that a comprehensive analysis of longer-period oscillations and trends has not been attempted.

      • Speed –

        Perhaps, if we look more closely, we’ll find this in the “Hockey Stick” papers somewhere:

        We deliberately limited this study to the period before 1960 because of the known divergence before this period, which means that a comprehensive analysis of more recent data and trends has not been attempted.

        But, I suspect we won’t. (grin)

      • Gavin,
        You know as well as I do that 1970 was chosen because that was when we had global satellite data. Your appeal to motive is rather pathetic! Is that the best you can do?

        PW

      • Your appeal to motive is rather pathetic!

        That was exactly the point of Gavin’s post…

      • A clever argument by false analogy.

        The core of the problem is the cavalier attitude with which you dismiss the divergance problem as an “issue to be resolved.” In fact, the divergence problem renders the entire project of treating tree rings as temperature proxies as a hypothesis that needs proving–not a presumptively valid methodology pending further analysis.

        Frankly, I think its insulting to our intelligence that you try this intellectual sleight of hand. Yet you get all huffy when people respond by saying they feel they’ve been deceived.

        Sorry, but an air of moral superiority isn’t going to carry the argument for you any longer.

      • And if we throw out all the tree-ring data, where does that leave us? Is there any historical record of the climate that is usable, or are we left with only trying to predict the influence of the rising CO2-levels by our understanding of the basic physics involved?

      • You’d rather use data that is known to be wrong than no data at all? Because not having such data would screw up the models?

        Bizarre and very dangerous.

      • No, that is definitly not what I am saying. But I am interested in the following: If we take that the tree-ring data is flawed, where does that leave us? Is there any other usable proxy data? Or do we do projections based on physics alone? And in the first case – what does that proxy data tell us about todays temperatures? And in the second – what does our understanding f physics tell us will be the consequence of increasing CO2? I.e. when the tree-ring data is bad, what do we actually then know?

      • This discusses the various types of proxies.

      • Yes, but it does not give the consequence for the theory of AGW. Which is what I am interested in, and what I hoped some knowledgeable person here could give me an answer to.

      • You’ve hit on the reason why these guys cling so ferociously to tree-rings. The evidence for AGW is not the result of scientific experiments, but theory and proxies. In a court of law, these would be considered “circumstantial evidence”. It is weak evidence, and every proxy that is eliminated makes the case weaker.
        Circumstantial evidence convicts people, though. You have to educate yourself and make your own decision.

      • But if we disregard the tree-rings and other proxies, we only have the physical models of how the greenhouse effect works. And these models tells us that CO2 is a greenhouse gas, and that if it is increased, the temperature will go up, does it not?

      • Thanks, Professor Curry, for addressing Gavin so directly and clearly.

        You offer him escape. He viewed it was a bridge he could cross to conquer his tormentors.

        Keep up the good work!

      • Good to see you trying to boost your ‘mate’ Richard Muller. He has been making ludicrous claims for years now and frankly, has little if no credibility whatsoever in this area.

        And how much money will he and you extract from this Berekely Temperature gig? You know the one, partly funded by Koch Industries…

      • You do know the CRU was initially funded by BP and Royal Dutch Shell…. Don’t you?

      • Tallbloke: Wasn’t one of the panel members, possibly on the Muir-Rueell panel also a BP exec?

      • For anyone else with a favourite conspiracy theory about CRU, there’s a list of CRU funders at the bottom of the CRU history page at CRU’s website. You can cherry pick funders to fit any Weevil Scientists narrative you want. Big Gummint’s in there, too. Knock yourselves out, they ain’t exactly a big secret. A bit like the Divergence Problem that anyone could have found in the peer reviewed literature for many, many years.

        http://www.cru.uea.ac.uk/cru/about/history/

      • It would be an incredibly convoluted way of going about making not very much money by going to all the trouble of setting up a special institute, publicising it, doing a lot of work, then trousering the loot with nobody noticing. Might as well go to Fred Cock and ask for a sub.

        But then. Didn’t ex Vice President Gore do something similar a while back?

        H’mmm…..

      • I watched Muller’s lecture. He seemed to make some good points to me and to be an articulate and credible speaker. And he has some documented credentials that I have checked.

        Can you point out specific things that you are unhappy with about it? Or do I just assume that a blanket condemnation from you should be good enough for me to ignore his arguments?

      • Well, for me a blanket condemnation by ianash is as good a reference as one can get. I guess it means I have to watch Muller’s lecture after such a convincing endorsement (ianash dis-approved) ….

        Ianash, please don’t leave. The forum will not be the same without you…/s

      • kai, what’s the betting that this new Berkeley temp group already ‘know’ what the answer to their study will be?

        Fuller can talk – he just cant do climate science.

      • And your qualifications for making this judgment are exactly what?

      • Umm, actually Ianash, as we’ve never met, to my knowledge, wouldn’t it actually be more accurate to indicate that I can write. BTW, you are correct, I don’t ‘do’ climate science. But I like to read it.

      • anash

        Here is the flow chart of government “funding”

        Tax from Companies and Individuals => Governments => Funding

        Where does ALL the government funding comes from?

        Reminder: Governments do not produce wealth.

      • JC: ” I would be particularly interested in hearing from any defenders of these global paleotemperature analyses by Mann et al.”

        Ok, sounds like you’re interested in having a constructive discussion and would like to understand where they (the “defenders”) are coming from.

        JC: “Continuing to defend these kinds of graphs is beyond anything I can understand.”

        Hmm, guess not.

      • Happy to hear your views on the analysis, but don’t use the graphs.

      • Great point!
        So much prejudits…

      • I don’t see a conflict in those two quotes. Well let’s combine them into a single sentence:

        I would be particularly interested in hearing from any defenders of these global paleotemperature analyses by Mann et al, as such a defense is beyond anything I can understand.

        Seems perfectly reasonable to me.

      • Judith,

        Agreeing to disagree is one thing. Calling other scientists dishonest and pseudo-scientists is quite another. That breaks down any constructive discussion that could have been had.

        Why be so strident and accusative? How does that jibe with wanting to build bridges?

        I agree with John N-G (http://judithcurry.com/2011/02/22/hiding-the-decline/#comment-45778 ), esp re the need for summary graphs and presenting the evidence with the highest confidence. I also agree with him that it would have been better if it had been better explained how the figure was arrived at. But broad brush accusations of dishonesty lower your credibility (with scientists at least).

      • But if a scientist stuffs up on an important issue with significant consequences and then either because they don’t understand, or don’t want to admit their mistake don’t man up (as it were), at some point other scientists need to call them out.

        Do you think they were wrong in their analysis and their presentation of their findings? If so have you publicly told them they should, in the interests of the reputation of all scientists, withdraw their results?

      • Bart

        I find it incredible that you believe Judith is the one losing credibility with (real) scientists here. The specious rationalizations offered in defense of this deception bring climate science into contempt and ridicule by anyone not so blinded by devotion to the cause that any offense against scientific integrity can be excused, rather than allow the dilution of the “message” .

        And yes, deception is the only appropriate word, this was not an accident, and was done for the intention of deceiving the readers. The accusation of dishonesty is made fairly, and is self evidently true. I urge Judith not to resile from it.

      • Verheggen-

        “But broad brush accusations of dishonesty lower your credibility”

        Taking the decline out, splicing temp records in, etc was all done because the original graph weakened the case – they had to doctor it to change it’s interpretation. That’s all documented.

        In what area of science does doctoring a graph to change it’s meaning fall within sound scientific principles?

      • ” Dishonest” is an accurate description Bart.

        If you marketed a Prospectus in which you deleted an inconvenient section of a graph, and replaced it with a different but more convenient graph, you would be on the receiving end of a lawsuit for false and deceptive conduct. No doubt about that.

        You do have to be obsessed to defend conduct which is plainly fraudulent in any world other than climate science.

      • Dr Curry,

        “Continuing to defend these kinds of graphs is beyond anything I can understand.”

        That really is the crux of the matter. It’s OK to make a mistake, so long as you’re prepared to admit it and fix it. Not to recant would appear somewhat churlish, but hell, some people are just too proud to say sorry. But to go on and on defending the indefensible, long after it has been pointed out in many different ways exactly why it is indefensible, is something else entirely.

        I believe the ongoing defence is perfectly easy to understand, but only if we allow a role for either dishonesty, or at least self deception. Gavin is strongly denying the former, so it must be the latter.

      • BRA-VO!

      • I hope there wont be an AR5. Better reread Lord of the Rings, or some other fantasy book. I am not interested in paying any more tax to these people. Whether birds fly into mountains, or frogs die of jumping too high because of some scenarios from a computer, is of no concern to me.

      • If you don’t like dishonest, try misguided and pseudoscience.” – Judith A. Curry, February 22, 2011 at 7:41 pm

        Pseudoscience is a meaningless word.” – Judith A. Curry, February 22, 2011 at 6:15 am

        What a difference a day 13.5 hours makes.

      • In which case JC’s response to GS was at the correct level

    • Gavin, I disagree with you.

      To build bridges, both sides will have to admit their mistakes.

    • Gavin;
      As per my statement below, you should really know when to give up. You simply make matters worse every time you defend on this topic. I would kick my student assistant half way down the beach (metaphorically speaking) if they even considered such an action.

      Shame!

      “With respect to Mann, Briffa, Jones et al. and all the other scientists that defended the original study and the hide the decline issue, as a geologist it strongly calls into question their impartiality as scientists. This then reflects on all of their other published work, and indeed the organizations that they work for (also the many researchers that work in their shadows)”.

    • Failing to mention in a Summary for Policy Makers that one key data stream supplying justification for claims that it has not been warmer for 1,000 years has serious problems–going out of one’s way to make sure that information is not available to policy makers–is characterized accurately by Judith.

    • Your credibility is not going in the direction you would like, sir.

    • You have gone significantly over the line with this post.

      What are you going to do, Gavin, present a lawsuit towards Judith?

      I find this tone of Gavin pretty remarkable, specially coming from someone who didn’t like the tone of another letter from E&E, asking for a retraction of Gavin’s criticisms of it.

      I guess free speech and free criticism only works one way, that is, Gavin’s way. How sad.

    • Gavin,

      Given that the MBH98 graph has caused so much misinterpretation since its appearance, you would surely agree that it would make sense to publish the same graph, restoring the “missing” paleo proxy data and removing the temperature series at the end. Your temperature series can then be placed on a separate graph alongside, with an explanation as to why the “hide the decline” controversy was mistaken. This would surely serve everyone’s stated purpose of making the science more clear – it would also be very easy to do.

      The next IPCC assessment report would be the perfect place to do it, thus avoiding a repeat of the political confusion caused by the original graph.

      What do you think?

      • Saad, where have you been the last 7 years. The entire Mann paper is faulty math. Have you not studied the decentered PC work of McIintyre, the bristlecone problems, and on and on?

      • Bob, I completely agree with you and I have studied Mcintyre’s analysis of MBH etc some depth, including the PCA analysis and the verification issues, but this was not my point.

        The point at issue as far as I see it is that the MBH98 graph in TAR was the piece of “evidence” that was brandished by most politicians as the rationale for carbon taxes, wind farms, mercury light bulbs and all the other costly and inefficient burdens we tax payers are now saddled with.

        To me it would be a very powerful symbol if the instrumental “splice” on the hockey stick were removed and the proxy data restored. The temperature graph can still be shown separately, but I think there would be a veritable Tsunami of “we were duped” from the world of politics if their main weapon of persuasion was shown to have been a “trick”, to use prof Jones’s words.

        It’s a much easier sell to show the visual sleight of hand that was used by the hockey team on MBH98 than it is to try and interest politicians in the more sophisticated statistical chicanery involved – Mann et al knew that the dry stats would make the pollies eyes glaze over, hence the pretty hockey stick graph.

      • …..oops….PC analysis or PCA, not both :-)

      • Well said Saaad, and good idea, but some how I don’t think the Hockey team is going to like it! :-)

      • I’m guessing you’re right, but there was no harm in trying.

    • Gavin writes:
      “Summary graphs are by their very nature, summaries.”

      How can you summarize that the tree ring data that you have collected for the last forty years shows a decline in temperatures when your thermometer data shows a rise. You cannot summarize a conflict. You have to announce that the last forty years of data undermine confidence in the earlier tree ring data. Anything less is not scrupulously honest.

    • I’d like to thank Gavin for reminding me of the utter lack of contrition exhibited by the RC and CRU crews on hiding the decline.

      I look forward to seeing the same cropped data series presented in AR5. After all, to remove or alter such an iconic series might lead me to infer there was some deceptive about the way it was represented. And about the people defending it.

    • Gavin, there are excellent references on how to make graphs to accurately inform. I highly recommend “The Visual Display of Quantitative Information” by Edward R. Tufte. Be sure to read the discussion of misleading graphicsAs for the graphics in question, if you prefer gross incompetence as an explanation, I don’t think it helps your case.

    • “It is therefore not surprising that they show only the reconstructions where the authors had confidence that the reconstructions were actually of the temperatures.

      Problems with modern divergence – which only applies to the Briffa et al curve in any case – are issues to be dealt with in the technical literature, as they still are. ”

      It is statements like this couplet that give rise to the accusations of your pathalogical dishonesty. Given the divergence from temperature, there is no justification for the confidence assigned to the reconstructions.

      We know that. So did your Teammates. That is why they tried to hide the divergence.

      You know it as well. You are too smart a man not to understand. You are simply too dishonest to admit it, and arrogant enough to think that you will get away with it.

      The ease with which you dissemble is disturbing.

    • Gavin: “Problems with modern divergence – which only applies to the Briffa et al curve in any case”.

      This is of course not true. There have been many tree-ring series which do not match the hockey-stick shape, thereby diverging from the favored narrative. Of course most these are never used in any reconstructions, but simply discarded.

      One can of course get rid of the divergence problem by choosing only the series which fit the intended/expected result, as has been done repeatedly, but this is cherry picking in its purest form.

      And cherry picking is not science.

    • Gavin said “It is therefore not surprising that they show only the reconstructions where the authors had confidence that the reconstructions were actually of the temperatures. ”

      Does Gavin see himself and his allies as gods who look down on data and decide that the bits they like are true and the bits they don’t like are false?

      Given that they can’t explain the decline, how can they know which bits of the record are accurate and which aren’t.

    • David L. Hagen

      Gavin

      Why are you justifying rather than correcting the chicanery exposed by ClimateGate emails?

      Deleting contrary evidence and claiming > 90% likelihood for what’s left, is so obviously unethical, that doing that in financial statements would land you in jail. That you defend this practice is so contrary to objective science that you show yourself wedded to your pet theory, regardless of evidence.

      Have you criticized those who opened the windows to defeat the air conditioning during Jim Hansen’s global warming advocacy at the June 1988 Senate Committee?

      Where are your objections to 90% of the USHCN weather stations having Urban Heat Island siting problems causing errors > 1 deg C? See http://www.SurfaceStations.org Have you insisted on correcting all the weather stations located near air conditioners or asphalt?

      In the mean time, US oil production peaked in 1970 and has dropped from >3 million barrels/day to 1.8 million barrels/day. The US now imports over 62% of its fuel consumption. The International Energy Agency (2010) reports conventional (light) global crude oil production peaked in 2006, and will not increase through 2035. Lloyds of London warns of a global fuel (“energy”) crunch beginning in the 2012-2015 period. Jeffrey Brown & Sam Foucher show that the rate of increase in China and India’s oil imports will consume ALL global oil exports by 2025.

      Where is there any serious evaluation by NASA of the rapid decline in available liquid transport fuels (“LIGHT OIL” not bitumen) compared to supporting IPCC’s wildly optimistic warming scenarios? The greatest harm caused by your arguments is that you are distracting Congress from this real severe decline in available liquid fuels that will very soon cause a massive economic crisis – far beyond the 2008 disruption.

      I can only conclude that NASA’s climate division is so thoroughly corrupted, that I support Congress’ efforts to strip all funding to analyze anthropogenic global warming, and return NASA to its original scientific mission.

      I encourage all readers to raise this issues with their Congressional representatives and Senators.

    • Gavin Said:
      Perhaps if I was to find a graph in one of your papers which I thought didn’t show some aspect of the data I was interested in, and then accuse you of dishonesty? Would you react well to that? This is exactly the same.

      Well, it sould only be the same if Judy hired a PR firm to run a web site to defend her study.

    • “Problems with modern divergence – which only applies to the Briffa et al curve”…

      Really?

    • “How can you claim to be building bridges, when you are so busy burning them?”

      I don’t speak for Dr. Curry, but Gavin, those bridges are not for you to cross. They’re not burning, still, they are utterly useless for you, because they lead in a direction you are unwilling to follow.

      That said, the best course of action for you and the Team you are intentionally attaching yourself to is to simply step down. It would be better for both science and the political cause you are trying to promote.

      For science it would certainly be better, as your personal contribution is minuscule so far. There are thousands of climate scientists who could do a better job, so you need not worry about your work being discontinued. Also, being a mathematician, with your modeling skills you could easily find a rewarding job in industry, admittedly with a somewhat stricter work schedule and less leeway for political blogging during office hours. Also, expect your computational models for industrial processes being audited every now and then, at the very least before their introduction to manufacturing or business where large sums of money are at stake. Finally, this move would make some contribution to restore the credibility of climate science and science in general in the eyes of the general public.

      It would also be better for your cause, as you lack even the most basic political skills. It is never good to mix science and politics, as it harms both badly. Of course scientists are entitled to their political opinions as private persons, but that should be kept painstakingly apart from their role as a scientist. As what you are actually doing is quite the opposite, your resignation would serve as a most needed warning for future generations of scientists. You should not deny them this enlightening experience.

    • http://wattsupwiththat.com/2011/02/22/realclimates-over-the-top-response/#more-34555. For more of Gavin’s increasingly bizarre behavior. There is a growing sense of desperation in the alarmist Fuhrerbunker.

    • “It doesn’t make much sense to include annual estimates, or seasonal estimates, or parts of the curve that the originators think doesn’t reflect actual temperatures”

      This is the problem. At this point the scientist in question is at risk of inserting their value system (or being perceived to do so) and should go out of their way to assure others of the precautions taken to guard against this possible corruption of the outcome.

    • Gavin,

      Why do you think you are in a position to tell others that they have gone “over the line” in a debate? Do you think you are the arbiter of the line? Especially given your recent post on E&E?

      Your style of debate is repulsive

    • “Honesty pays, but it don’t seem to pay enough to suit some people.”

      — Frank McKinney Hubbard

    • Richard S Courtney

      Gavin:

      Your obfuscation and personal attacks on Dr Curry are reprehensible.

      The facts are
      (a)
      The tree-ring proxy data indicated declining temperatures after 1960.
      (b)
      The thermometer-derived data indicated rising temperatures after 1960.

      These facts indicate that
      1.
      The tree-ring proxy data are wrong
      Or
      2.
      The thermometer-derived data are wrong.
      Or
      3.
      Both the tree-ring proxy data and the thermometer-derived data are wrong.

      Those findings are the only significant results of the MBH studies that provided the infamous ‘hockey stick’ graphs. And they are important findings.

      But the MBH papers did not assert those findings. Instead, those papers used ‘graphology’ to “hide the decline” in temperatures after 1960 that was indicated by the tree-ring proxy data. And the ‘climategate’ emails prove that the ‘graphology’ was not merely incompetence but was “Mike’s Nature trick” being used to deliberately misrepresent those findings.

      So, “Mike’s Nature trick” was either corrupt scientific practice or pseudoscience: there are no other possibilities.

      Please remember that I have continuously complained at the splicing of the two data sets from the first week after publication of MBH98 (i.e. since long before the McIntyre demolitions of the MBH studies).

      Indeed, you left a closed Climate Science discussion forum (of which we were both Members) in a huff because you could not cope with my pointing out your egregious scientific errors.

      Your obfuscations, posing of straw men and throwing insults like confetti do not – and cannot – distract from the fact that “Mike’s Nature trick” was either corrupt scientific practice or pseudoscience. In my opinion, the only hope you have for a way back from where you are is to abjectly apologise for having done it, and that hope may be forlorn.

      Richard

  7. “group that hid the decline”

    “not in the discovery mode, they were in the reporting mode”

    Poor Mr. Muller.

  8. Gavin,
    honestly, one can strive to bring bridges, but not please over this disgraceful episode. Let’s get over it with some acknowledgement that is should no have happened, and that it shouldn’t happen again. Dishonesty and similar adjectives refer to subjective states, and are clearly debatable. Trying to convey a non-diluted message might be a “noble cause”. However, the thing was not done well at all, and in fact backfired (the backfiring started in 2002-2003, and continues backfiring). One does not have to subscribe all words said against the CRU Team or Mann to agree that the episode had better not happened at all.

  9. This quote from Briffa in the main thread – “The cause of this increasing insensitivity of wood density to temperature changes is not known, but if it is not taken into account in dendroclimatic reconstructions, past temperatures could be overestimated” should have ended …”underestimated”. Briffa and Mann wanted their tree rings to show coolth 1000-1300 relative to warmth in 1950-2000; the tree rings for that later period showed coolth not warmth, which had to be hidden in TAR and AR4, because it was likely they also showed coolth instead of the actual warmth in the MWP. Briffa was either being as disingenuous as Mann or showing equally poor grasp of English. The real problem of course is that tree rings are lousy proxies for temperature.

  10. There will always be a need for summary graphs, in all branches of science, for communicating the main points to a broader audience. I have seen, and continue to see nothing wrong with using a summary graph, intended for a broader audience, to show only that segment of data with which the scientists have confidence.

    The divergent data post-1960 fits into the category of less-reliable data, as does the Briffa time-series that is deficient in long-term variability (Gavin is right that this was the subject of the ‘dilution’ email.) I have no objection with any of the figures mentioned in the post.

    I do, however, object to insufficient explanation of how the figures were constructed, and why. Even Gavin agrees that the WMO figure was poorly documented. I go farther, and agree with you that there was insufficient discussion of problems with reconstructions in the IPCC TAR and AR4 reports. The authors should have been more even-handed.

    Regarding the “likely” statements, the problem there is that the IPCC reports are written primarily by in-field experts. The NAS Hockey Stick panel, by contrast, was a mixture of in-field and out-of-field experts, and the committee did not bestow on the in-field experts the assumption that their methods were reliable. The NAS panel produced a more credible document because of it, one that is still quoted by **** and **** alike (insert your favorite catch-all terms). This is a structural problem with the IPCC, not a problem with the IPCC authors themselves.

    Judith, please be more specific when you say “any defenders of these global paleotemperature analyses by Mann et al.” If Mann et al. thought that their original hockey stick analysis was a sufficiently accurate temperature reconstruction, they would not have spent the following decade trying to come up with better reconstructions.

    • John, the more recent reconstructions still suffer from the same problems: uncalibrated proxies, and statistical models that make no sense in terms of calculating hemispheric or global average temperature anomalies.

      • You betray complete ignorance of any of this literature. “Statistical models that make no sense in terms of calculating hemispheric or global average temperature anomalies” – got a cite for that?

      • Another zinger, I’m dying here.

      • Hey, I just asked for a justification for your sweeping statements. Perhaps you think that the new ‘blog science’ can dispense with old fashioned concepts like references? I obviously have much to learn.

      • My detailed justification of this statement will be forthcoming at another time, in fact I will make it the subject of a thread at Climate Etc. sometime in the near future.

      • Of course it will.

      • You are a Pit Bull, aren’t you?

      • I’m delighted to hear that you are looking forward to it.

      • Dr Curry,

        I am at a loss to understand what Dr Schmidt thinks he is achieving here. My first encounter with the hockey stick sent me searching the web for information and I was, at first, delighted by my discovery of Real Climate. However, after few weeks reading I saw that the bullying and bluster towards anyone who dared to question the Party line was a symptom of something deeper, a commitment to a flawed paradigm that could allow no dissent because one failure would cause the whole thing to softly and silently vanish away. Hectoring and bullying make me suspicious — not being able to follow the science beyond a basic level I have to judge the scientists by their words and actions.

        Dr Schmidt, as a layman I find your attitude to dissent so pathological that not only do I distrust your climate opinions, I wouldn’t let you sell me a pound of sausages.

        Persuasion to the Real Climate point of view is possible only if those who write there, and here, remember that people are suspicious when reasonable questions about disputed science are met by an extraordinary exhibition of affronted pique and wounded amour-propre such as the one above. Most important, remember that people react badly to bullies. Speak softly and bear the sword of good science, otherwise you will persuade no-one.

        Julian Flood

      • Well said, Julian. I know we shouldn’t necessarily judge the message by the messenger, but sometimes, the two are related.

      • “Dr Schmidt, as a layman I find your attitude to dissent so pathological that not only do I distrust your climate opinions, I wouldn’t let you sell me a pound of sausages.”

        Very nicely put. The Team have lost all credibility as
        scientists, and act purely as activits and propagandists.

        Which again makes me wonder: How does someone who
        has so clearly made the move from scientist to activist
        retain their credibility as scientist? In my mind you
        cannot be both, because a scientist is supposed to follow
        the truth whereever it may lead him/her, whilst an
        activist has a predefined agenda.

      • Julian, it looks to me like Gavin asked for elaboration. He was practically asking to be corrected in his statement that she “betrays complete ignorance of any of this literature.” It’s her blog, let her state specifics and make specific references, if she has them.

        It sounds like something that could be countered pretty easily to me, but hey, I’m just a layman like yourself. But whatever your occupation, when one wants to get things straight, one is direct.

      • Speaking as a layman, I am delighted that Gavin has posted here, since it allows us to see how vapid Curry’s replies are.

      • This is brilliant! Two heavyweights of climate science finally face to face in the public arena. Are we finally about to have the debate we were all told was “over”? I certainly hope so!

      • I know, right? Curry looked pretty helpless when it was just her and the other scientists. She had to get some non-experts in here from WUWT or it would have started looking like a rout!

      • Wouldn’t it be more helpful if everyone tried to check their sarcasm at the door and addressed the issue at hand?

        Anderlan, what are your views regarding the ethics of “hide the decline” and the hockey stick graph?….and can you express yourself without any sarcasm or personal attacks?

      • Craig Goodrich

        Easy, Gavin. I hope you are bearing in mind that it’s only because of academics like Dr. C that the term “climate science” is not regarded as an oxymoron.

      • Well said Craig!!

      • It is thanks to the efforts of Judith Curry, Eduardo Zorita, Hans von Storch and like-minded honest and objective ‘warmist’ climate scientists that many ‘deniers’ like me hesitate to dismiss climate science as “horoscope science” and climate models as “astrological charts”.

      • I still make a practice of distinguishing climate “science” from climate science.

        Schmidt’s deranged bluster speaks of an incomplete theory of mind – he clearly cannot understand the damage he does to his cause every time he writes a word outside his own echo chamber.

      • Do we now have a cite for:

        > Statistical models that make no sense in terms of calculating hemispheric or global average temperature anomalies.

        ?

      • It’s a cliffhanger, willard. The blogospheric equivalent of “tune in again next week for another exciting episode of…”

      • Gavin,
        Try Mann’s Nature article where a few sediment cores off long Island became (I hate to say it) a global tropical cyclone hockey stick. Please defend what I think is one of the worst Nature articles I have ever read. Imagine if these sedimentary sites were matched with TC hits in the NATL (pretend they were met stations). How many TCs would it have found? How many winter NE’ers?

        And, BTW, we chose one data source for our paper on TC intensity. Turned out that we should only have used since 1980. References for that if w]you want. But I suppose we could have gone back pasting these satellite images since 1970 (0r 1980) with a bristle cone here, a coral reef there and come up with a global trace of whatever for a 1000 years.

        I have no real argument about using various proxy data to reconstruct things but I think that one has to take it on the chin and look carefully at what errors andre and what endless defense of questionable data and statistics has done to the field.

        It 2 a.m. in Bangkok and I am going to bed.

        I think your appeal to motive, statements about crossing a line are out of place and have done and continue to do immense harm. That is not a legacy I would like to have.

        PW

    • And why wouldn’t the scientists have any more or less confidence in the data post 1960? because they don’t agree with instrumental record? To my mind, this is sufficient justification to have no confidence in the entire time series before 1960 as well.

      • Try actually reading the papers on the subject, and perhaps you would be less confused. Start with briffa et al (1998):
        http://www.nature.com/nature/journal/v391/n6668/abs/391678a0.html
        Briffa et al (2001):
        http://www.cru.uea.ac.uk/cru/people/briffa/jgr2001/Briffa2001.pdf
        or
        D’Arrigo et al (2007):
        http://www.ldeo.columbia.edu/res/fac/trl/downloads/Publications/divergence2007.pdf

        But if you think that the divergence problem makes Briffa et al (2001)’s reconstruction unreliable for whatever reason, go ahead and ignore it. It doesn’t affect Moberg et al, Ljundqvist 2010, Mann et al 2008 or Osborn and Briffa (2006). And it doesn’t make Briffa dishonest.

      • Great, thanks for the references, glad to hear that divergence is no longer a problem.

      • I think if you just go right to the source and ask one of the original authors of MBH, you might gain some particular insights and reaffirm that your instincts were correct about the validity of these “hockey stick” reconstructions.

        Dr. Bradley, how certain are you in your MBH paper going back 1000 years?

        Dr. Bradley: “….but we could only do this back to about 1700. Whether we have the 1000 year trend right is far less certain ….”

        http://climateaudit.org/2011/02/21/we-could-only-do-this-back-to-about-1700/

      • Your losing what shred of credibility you had left Judy. Gavin offers you science. You offer snark and defensiveness.

        How about you review the papers rather than trying to excite the denialists?

      • No, he offered papers on tea leaf reading. And it seems the alarmists are the ones that are animated. How radical that Dr. Curry is against intentionally misleading graphs.

      • She is chumming and you know it. This is old news, regurgitated by Curry to stir up the natives.

      • “…stir up the natives.”

        Such insensitive language, ianash. Sounds like something Rudyard Kipling would say. Do you really think someone with your colonialist mentality should be the first outsider to visit the mysterious aquanaut-people of Sri Lanka? And we’re talking about Sri Lanka, ianansh–a country with a cruel history of Western imperialist exploitation. Not to mention the carbon footprint of your journey and the high-carbon, Westerner-needs, logistics strain your stay would place on Sri Lanka’s flood ravaged infrastructure.

        Save your money, ianash, and stay home–send a contribution, instead, and confine your volunteer work to needs within cycling distance of your residence.

        It’s about eco-trips, ianash, not ego-trips.

      • Oh Archie, turn the tv off for a while. Stop watching Glenn Beck. Your brain will thanks you for it.

      • You know, ianash, one of my little tricks that I employ with you is to provoke you into making remarks that are so repellent that they stand, unadorned, as stink-bomb monuments to your trollery. Another trick is to keep you going until it becomes clear to all that you’ve been out-classed.

        Mission accomplished, once again.

      • Curry – perhaps you need to take Tallblokes teeshirt off – it seems to have strangled your brain and also removed any hope of reconcilliation,

      • Don’t forget reconciliation has another dictionary definition. A more scientific one. It is the totting up of all the sub totals to see if they match the headline figure.

        In climate science terms this means checking that the sub-hypotheses and claims stack up to the main claim that:

        Most of the observed increase in global average temperatures since the mid-20th century is very likely due to the observed increase in anthropogenic GHG concentrations.[7] It is likely that there has been significant anthropogenic warming over the past 50 years averaged over each continent (except Antarctica)
        http://www.ipcc.ch/publications_and_data/ar4/syr/en/spms2.html

      • Have you checked with the Vice Chancellor about my letter? Did it arrive?

      • Thanks for the information, I’ll email his secretary this morning for a copy.

      • Do ask the VC if we can share….

      • The VC’s PA has responded, and the matter is in hand.

      • Ianash, you forgot to include “funded by Koch…” in your last reply. That is now required in all attacks on “deniers” by defenders of the faith. Please remedy this deficiency immediately, and, please, read your emails, didn’t you get the message ?

      • @j.curry
        “Great, thanks for the references, glad to hear that divergence is no longer a problem.”
        Instead of this “answer” I would have appreciated an argument on Gavins point:
        What about reconstructions with data (also tree rings!), which show no divergence problem?

      • Isn’t that the definition of cherry picking? Avoiding the data that refutes your hypothesis and simply pointing at data that doesn’t?

        Hypothesis: All swans are white
        Observation: One black swan.
        Rebuttal: But look at these 100 white swans!

      • edit: “All swans are *white*”

        Too little sleep lately :)

      • Au contraire.
        Reminding of Judy to look at the full body of paleoclimatic evidence isn’t at all “cherrypicking”. And by the way, MBH fits very well to this body.
        Can you cite only one reconstruction, which doesn’t show a hockeystick (shaft spaghetti-like or not)? Seeing the endless discussion of the “ancient reconstructions” of Mann or Briffa in skeptic blogs is pointless, because since then we have so many hockeysticks, the Mac’s have to work much harder to refute them.

      • My point still stands. We found a black swan, and all the white swans you point at don’t make the black swan go away.

      • I still do not understand your swan-analogy.

        What is the white swan? The hypothesis, that recent warming is unprecedented in the last 1000 years? Or the hypothesis: “Our Tree ring data before 19xx are reliable.”? Choose yourself, I paraphrase the discussion:

        MBM and Briffa said: “We observed white swans.”
        Curry: “I don’t trust your observation method. I’m not convinced, the swans are white.”
        Gavin: “But we have a lot of examples, where unequivocally white swans were observed.”
        Curry: “Mann, Briffa, IPCC are dishonest”
        Others: “Can you prove? Have you references?”
        Curry: “I have to read and will answer later.”
        Others: “Did you observe a black swan?
        Curry: sigh

        (By the way: Your black and white swan example show some insight in theory of scientific knowledge and Sir Karl Popper. Please take into account, that even it were true that the methods of Mann and Briffa were false, then it’s not logical to suppose the opposite of their findings to be true.)

      • Here’s a better paraphrase:

        MBM and Briffa: “We’ve observed white swans.”

        MBM and Briffa: “Oops, my bad, we just saw a black swan. Let’s just ignore it.”

        Curry: “Wait a second. You guys found a black swan!”

        Gavin: “The black swan doesn’t count! I’ve got three more white swans to show you right here!”

        Curry: “You guys aren’t doing science. You’re either being obtuse or disingenuous.”

        Gavin: “Stop calling me names! You don’t know what you’re talking about! You’re a mean person! My feelings are hurt and you’re ignorant!”

        As I see it, we’ve got one dendro proxy that was used to assert that recent warming is unprecedented. But it didn’t cooperate, and diverged from reality. Other similar dendro series may not have been observed to diverge from modern reality, but the *one* failing dendro series casts doubt on the utility of *all* dendro series.

        If you believe trees can tell us about ancient temperatures, you cannot simply cherry pick the trees you want to use as thermometers.

        Put another way, with hind casting, let’s say I found a dendro series that perfectly matched the past 10 years of recorded temp data. And it just so happened that this dendro series showed that 1200 AD was 200C hotter than today. Obviously we wouldn’t assert that the obviously false signal was true simply because it matched up with modern data for some period of time.

        Trees are not good thermometers, and the one “black swan” has shown that. While you may be able to cherry pick “white swans” that *look* like good thermometers with the data we have, I’ve got no confidence that it means they will continue to be so in the future.

      • @ jere

        Ah, now I understand your swan-analogy, but I can’t agree. The main reason is, because as a scientist you have always to regard the full body of evidence. You are allowed to dismiss data only, if you have good reasons, that they are not reliable. So if I adept your point of view, all you can do is to dismiss the results of Mann and Briffa, but after that you have to look at the rest.
        I’m sure, you will not agree to this point and maybe you will have good arguments.

        But I would be glad, if you could say, you understand also my point of view.

        Best regards

      • @andreas:

        I do understand your point view, but I think that the “full body of evidence” metric is of doubtful utility. Let me use a different scientific topic to demonstrate->

        The “full body of evidence” on diet and nutrition is generally in support of a low-fat/low-calorie diet. However, this is mostly because the study there has been notoriously myopic, concentrating on finding more support for their theory, rather than on falsifying it. We’ve got hundreds, upon hundreds of studies that have been done, and found some sort of support for that theory, but the truth, as documented by Gary Taubes in “Good Calories, Bad Calories”, is that these observational studies are terribly, terribly flawed, and when evidence has been found that the hypothesis is wrong, it’s been carefully ignored.

        So, the problem here is that negative results are either ignored, or suppressed, and anything with the slightest support is touted to the hills. This is a significant flaw in the pursuit of science. And because of this, because people in the science of diet and nutrition ignored this flaw, and based on a “preponderance of evidence” and the precautionary principle, our health authorities have suggested for the past 40 years that we eat less fat, and more carbs, we’ve suffered through four decades of obesity, diabetes, heart disease, cancer and other chronic diseases related to carbohydrate intake. The *best* of intentions here caused *incredible* harm.

        Back to briffa’s dendro, I get the feeling like they’re dismissing data not because of “good reasons”, but because it does not support their hypothesis. As for “look at the rest” (which I assume means other lines of evidence), I’m happy to look at it, but it doesn’t strike me as particularly convincing. I want someone to look *really hard* for a black swan. I want them to spend an entire lifetime trying to falsify their own hypothesis, looking for any shred of data that might prove them wrong. I want them to be constantly thinking about how they could be incorrect. And if despite all of these attempts, they fail to falsify themselves, then I’m going to be convinced.

        As a fairly well informed layman, I must say, I’ve got the distinct impression that many of these researchers (Mann in particular), aren’t interested in the least in falsifying themselves. Now, this may not be true of all AGW researchers -> maybe Mann is just a particularly bad apple -> but there you have it, that’s the public perception.

      • andreas –
        I would suggest you read some archaeology texts – preferably those written before 1998. Although most of the ones written after that date still show the evidence, they also include disclaimers wrt GW/CC. It’s how they get published. Even when the evidence directly contradicts the pro-cAGW statements.

      • Andreas, you need to look a little harder at the reconstructions, if you simply accept what you are told at face value you miss a lot of information. The reason that other reconstructions show similar results is that with exceptions, they all use the same subset of proxy data. Many in fact use the MBH98 PC1 as a proxy itself, which is kind of insane when you think that people like Gavin think that this is “independent” !

        Also, in many reconstructions, the methods used are quite specifically designed to select and heavily weight proxies that do fit the modern temperature record, regardless of whether they are indeed actual temperature proxies (can we say, contaminated lake sediments or strip-bark bristlecones ?).

        You can find many dendro proxies that show the late 20th Century decline, in fact I assert that the majority probably exhibit that behaviour, however those dendro proxies are rarely included in reconstructions, with the result that, as noted above, the same small subset of data ir re-used over and over again. And, what is worse, in some cases the original data has been re-sampled with differing results, and in at least some such cases the reconstructions use the older sets if they show a more significant 20th Century response. Examples, bristlecone pines (Linah Ababneh’s more modern and comprehensive data collection looks nothing like the earlier Graybill samples that oversamples strip-barks), yet Ababneh’s data is NOT used; and the Polar Urals proxies, same problems. Such behaviour HAS to be called disingenuous at best, deliberately deceitful and dishonest would however be a better description. Gavin, defends such behaviour, which speaks absolute volumes about his commitment to the deceit.

      • Mann et al 2008? You just kidding right?

      • Where is Briffa?

      • On holiday. Yamal Peninsula. The trees are warm there at this time of year.

      • Ever see “Weekend at Bernies” ?

      • Dr. Schmidt,
        Is it not incredibly ironic that the this sort of conversation cannot happen at your Soros funded blog?

      • Thank God real climate doesn’t let this sort of conversation happen, which basically consists of Judith Curry launching unsourced ad hom attacks against various scientists, with piling on by random posters.

        Thus far, Judith’s justification consists of:

        My detailed justification of this statement will be forthcoming at another time, in fact I will make it the subject of a thread at Climate Etc. sometime in the near future.

        Some might think that justification might *preceed* an attack, or at least be part of it …

      • Yeh, because being against obvious deception needs additional justification.

      • Yeh, because being against intentionally misleading graphs needs a lot of justification.

      • I agree dhogaza.
        This superficial blast of hyperbole by Curry will be instantly disregarded as rubbish by one and all as decreed by Darth Gavin.

        “These are not the droids you looking for”

        Once again you are proven right.

        Hail to the REALCLIMATE

        Zorro

      • It won’t be ignored by the voters who control Congress, which controls the purse strings of the nation. CO2 and AGW is about money. As the funding dries up the house of cards will crumble. You can fool some of the people all of the time, and all of the people some of the time, but you can not fool all of the people all of the time.

      • Where are her ad hominem arguments? Do you know what an ad hominem argument is?

        Mark

      • Dhogy,
        You are soooo right. I too am thankful that Realclimate provides a safe sand pit for right thinking little commissars like yourself to play in, away from all that corrupting free debate that adults engage in.

      • well said Jim well said.

      • I agree too.

        High five!

        Go Team Skeptic!!

      • If you are in too much of a hurry to troll away that you fail to read the article, which contains more than adequate justification for Judiths claims (which are not ad hom in any way – dishonesty is dishonesty, ad hominum doesn’t come into it), how about leave the discussion to us grownups

      • Jesus wept ! The dhogaza complaining about ad hominem attacks ! The fool doesn’t know anything else. He is stunningly ignorant of science and appears to know nothing of honesty or ethics. If it wasn’t for the howlers he comes up with you’d have to think him a badly programmed bot set up by Fenton, but even they aren’t that stupid, are they ?

        Push off Hog, stick to Realclimate (ha!) where the claque of sycophants can cheer you as you fearlessly attack those who are denied the opportunity to respond.

      • A complaint about “ad hom attacks” coming from you Dhogaza is laughable.

      • NOT Soros funded, it’s TAXPAYER funded.

      • RC is not taxpayer funded. NASA is, however.

        Mark

      • And, as NASA employees are running RC during work time….

      • Gavin,

        the papers that wave their arms and suggest the decline is anthropogenically caused?? Isn’t AGW amazing? It can cause anything that supports your meme, as long as you are not required to show explicit data and observations as support for the suggestion!!

      • RE: “briffa et al (1998):”

        The AGW virus can be recognized by the following signature

        valadj=[0.,0.,0.,0.,0.,-0.1,-0.25,-0.3,0.,-0.1,0.3,0.8,1.2,1.7,2.5,2.6,2.6,2.6,2.6,2.6]*0.75 ; fudge factor
        yearlyadj=interpol(valadj,yrloc,x)
        densall=densall+yearlyadj


        It currently appears that patient zero was an IDL program known as “FOI2009/FOIA/documents/harris-tree/briffa_sep98_e.pro”.

        http://www.thespoof.com/news/spoof.cfm?headline=s5i64103

      • Andrew why are you still repeating this garbage. I pointed out on another blogthat a later programme does not have any fudge factor
        ARTIFICIAL CORRECTION ;****** APPLIES A VERY ARTIFICIAL CORRECTION FOR DECLINE********* comments:
        see:
        recon_tornyamataim.pro
        this seems to be the later version of your files:
        densadj=reform(rawdat(2:3,*))
        ml=where(densadj eq -99.999,nmiss)
        densadj(ml)=!values.f_nan

        Note no yearlyadj no valadj

      • This is an interesting comment. Gavin invites JC to ignore Briffa 2001, which is good in a way, because this is the point I think she was trying to make – namely that the Briffa series should not have been used at all in the WMO and IPCC reports because the divergence suggested that its growth was affected by factors other than temperature. As we know there is little or no evidence to suggest that this factor is restricted to the post-1960 period, and there was certainly none at the time of the WMO report and TAR. Leaving the pre-1960 section in was therefore misleading.

        The other papers Gavin cites strike me as a red herring. We are discussing the treatment of the Briffa series in summary reports. These other papers are therefore irrelevant.

      • Yes, throwing sand in JC’s face, I think.
        It’s a tactic that might work against a non-scientist, of course…

        [Look at my fabulous peer-reviewed evidence!]

        Since everyone’s wading in on this thread, I’ll just add my 2 cents: this needed to be said, Judith, well done.

        Of course, the hockey stick graph was a political tool and has served that purpose admirably.

      • Have you actually READ the Ljungqvist paper? I Google’d for the original graph as shown in paper (I have read the whole paper), and this is what it looks like:
        http://i54.tinypic.com/11wd2r5.png
        (note that the last proxy based 10 year average is from the 90’s so there is actually not much missing incline in the proxy data)

        Ljungqvist also states that:
        “”a very cautious interpretation of the level of warmth since AD 1990 compared to that of the peak warming during the Roman Warm Period and the Medieval Warm Period is strongly suggested.”
        Which is a reasonable statement since proxies are no thermometers therefore they are not comparable. You compare proxies against proxies and thermometers vs thermometers, period. And I think Ljungqvist is the best judge on his data.

        But what instantly happened was that some blogs like SkS plotted crutem on top of that with a Mannian smoothing to show a huge overpronounced incline and declared this as a hockey stick. IT IS NOT A HOCKEY STICK IF YOU LOOK AT THE ORIGINAL PAPER.

        And I dont see almost any other of those “hockey stick”‘s (like Moberg) to show “unprecedented” temperatures unless an apples to oranges -comparison with thermometers is being used.

      • Sorry G,
        Mann 08 is nearly as ugly as Mann 98. Tiljander is your first clue. Carry on…

      • Do not assign homework. If you can’t defend the matter in your own words, you do not understand it. And we doubt that you understand it.

      • But isn’t multi-variable statistical analysis able to separate the times when one variable affects the desired dependant variable from the times when it doesn’t by the use of priciple component analysis?

        The point being that temperature is not the only variable affecting tree ring growth, but the statistical methods can pick out when it does. I have colleagues (I am not that familiar with the statistics) who have used similar methods to resolve different variables effects on a final dependent variable. So I find that saying that because of the divergence problem, then the whole of dendochronology warrants no confidence is unjustified.

      • Exactly, since the PCM method should separate out the temperature, the fact that there was a divergence is extremely significant. Any factors other than temperature that were causing the divergence should have been filtered out, leaving only temperature, which should have shown no divergence. But there was a divergence, so the technique and/or methodology employed in the study must be flawed and the conclusions cannot be relied upon.

      • Um, no, that’s a silly assertion. PCA does not attach labels to the outputs that say “temperature,” “sunlight,” etc., if the input sources combine non-linearly, or they change over time, you cannot separate them using linear extraction techniques. If your colleague is doing that with “similar methods,” such methods are either not so similar, or they have other information that relates the inputs to the outputs, e.g., he knows how the inputs relate to each other with time.

        So I find that saying that because of the divergence problem, then the whole of dendochronology warrants no confidence is unjustified.

        Who said that? It just means tree rings aren’t good thermometers.

        Mark

      • that is the point i was making through contradiction. PCM cannot distinguish if tree growth declines because of excess heat, cold, wet, dry. as such, the hockey stick could be measuring any of these factors, at any time, depending which one was thaving the most effect. the post 60’s decline showed they were not measuring temperature, but the ignored it. worse, they hid it in the bottom of a locked filing cabinet stuck in a disused lavatory with a sign on the door
        saying Beware of the Leopard.

      • that is the point i was making through contradiction. PCM cannot distinguish if tree growth declines because of excess heat, cold, wet, dry. as such, the hockey stick could be measuring any of these factors, at any time, depending which one was thaving the most effect. the post 60’s decline showed they were not measuring temperature, but they ignored it. worse, they hid it in the bottom of a locked filing cabinet stuck in a disused lavatory with a sign on the door
        saying Beware of the Leopard.

      • Precipitation affects growth, but in the far past you do not usually have data on precip to factor it out and infer temp.

      • I’m confused by this argument. If you are claiming that the people in question intentionally misled us by the way they presented the data, isn’t the important issue what THEY thought about the quality of the data rather than what YOU think of it?

      • It’s a matter of opinion then?
        The quality of data is based on the ability of said data to demonstrate warming in my opinion.

      • John n-g If you are claiming that the people in question intentionally misled us by the way they presented the data, isn’t the important issue what THEY thought about the quality of the data rather than what YOU think of it?
        Yes. It turns out they were worried that it “diluted” their preordained message.

      • John N-G

        “isn’t the important issue what THEY thought about the quality of the data rather than what YOU think of it?”

        Only if they were the only ones who were going to see the graph. The graph, while a summary graph, was specifically designed to convince people of something. The change was made to make it more convincing, not because of some idea that scientifically one way was better.

        As the communicators, they had a responsibility to show IN THE GRAPH the main features of the data sets so viewers could see for themselves. It’s also up to the communicators to make sure that what they present is the most likely presentation to try to make sure a clear and true picture will be received by the audience. I doubt you’ve read McIntyre’s documentation of this particular incident, but if you have I think you need to do a professional ethics check.

      • Harold- Thanks for the on-point response. I think one of the things that led everything astray was that in the original WMO figure, the authors were tasked to show global temperatures over the past 1000 years, not specifically tree ring data. So there was no point in showing the portion of the tree ring reconstruction that clearly DIDN’T represent global temperatures.

        We can turn that around, though. What’s the point of showing both tree ring reconstructions and global temperature measurements during the calibration period where they overlap? During that segment of the reconstruction, the tree ring data is literally nothing more than an approximation to the global temperature measurements that are also shown. There’s absolutely no point in showing them both, and it leads to a false sense of confidence in the tree ring reconstructions for anyone not familiar with how they are made.

        I really don’t think this was part of the conscious thought process of those who created the graphs, but it’s important to explore these issues so that (a) similar problems don’t arise in the future and (b) there are no excuses if they do. At least, I think that’s the stated purpose of this blog item.

      • Well I *do* think it was part of the conscious thought, and I *do* think this is all-too-obvious. Further, if your claim that these people weren’t doing bad things knowingly, then with all due respect, fire them immediately. You cannot have it both ways. Either they are intentionally disingenuous or they are incredibly incompetent. Remember that these people *still* give you this kind of graphic mish mash.

      • Not to throw out the baby with the bathwater, but if there was a recent 40 year period of no correlation how does it hold that the rest of the series has any correlation at all with temperature? Seeing as they were forced into correlation during the calibration period, were incorrect for the recent period, why are they of any worth in the preceeding period?

      • Dr Curry,
        “To my mind, this is sufficient justification to have no confidence in the entire time series before 1960 as well.”
        Thank you for saying that. Why oh why has it taken so long for an “insider” of the climate science community to state this simple and obvious truth? Of course, I suspect your status as an insider is well and truly under review by the club. Let’s just hpe that a tipping point has been reached, and the members are of a mood to vote out the current board.

    • The divergent data post-1960 fits into the category of less-reliable data

      This is pretty remarkable on itself. It shows why I have lost (some) confidence on climate science over the past few years. Mr John, “data” isn’t “less reliable” only when it shows you outputs that you don’t like. If a model, say, a paleo reconstruction, gives you a completely bad output in exactly the best years it had to show that it worked well against actual thermometers (despite the calibration years), it destroys the credibility of the whole reconstruction.

      How this basic fact is simply handwaved as a “it’s only a post-1960s problem”, is astonishing to me.

      And then this:

      If Mann et al. thought that their original hockey stick analysis was a sufficiently accurate temperature reconstruction, they would not have spent the following decade trying to come up with better reconstructions.

      I really have to self-snip what I really wanted to reply to this kind of sheer naive optimism. Hadn’t McIntyre et al fought like hell to show what MBH already knew were bad practices and faulty statistics, we wouldn’t have had Mann2008, etc.,etc.. The only “benefits” of the latest installments of the hockey stick is that now they can testify that their model is sufficiently hacked to the point that no longer can anyone say that the graph is entirely dependent on bristlecones. I guess 10 years is enough to find other “good” proxies for that kind of job.

      • Robert Leyland

        The divergent data post-1960 fits into the category of less-reliable data

        … and this is scary because that overlaps the time period of “maximum CO2 influence”

        Also commonly claimed by AGW proponents: It can’t be the Sun because TSI doesn’t match the temperatures post 1970.

        and yet tree ring declines post 1960 are hand waved away – amazing!

      • Regarding your first point, I agree with the problem but disagree with the solution. Lack of agreement with recent data does decrease confidence in the rest of the reconstruction, but I feel this should be expressed better as increased uncertainty ranges during the reconstruction period. Alas, uncertainty bars traditionally represent the known unknowns (because these are the only ones that are quantifiable), making them inherently misleading. This is a problem throughout science, not just climate science.

        Regarding your second point, McIntyre et al deserve some credit, but it strains credulity to think that the entire paleoclimate community would have been satisfied with the very first attempt at global reconstruction and said “Nothing to improve here, may as well go flip some burgers”.

      • I think you misunderstand how PCA works. Divergence indicates a non-linear and/or non-stationary relationship between the output (ring width, density, etc.) and the inputs, the sources one is attempting to extract. Increased uncertainty is not what you get unless floor-to-ceiling is what you call increased.

        Mark

      • This is shear madness.
        The part of the paleo record that we can accurately calibrate against temperature shows that trees are not reliable thermometers, so your solution is to deem the most accurate calibration segment the data as “faulty”. But the prior data, going back centuries where there is no reliable cross calibration, can still tell us something? Particularly when it is used to show that temperatures in the past weren’t as high as today?
        The only sensible solution is to conclude that paleo studies provide no accurate temperature history. There are no “error bars”, it’s just all error.

      • Lack of agreement with recent data does decrease confidence in the rest of the reconstruction, but I feel this should be expressed better as increased uncertainty ranges during the reconstruction period.

        But that would require another statistical model that would calculate just how much decrease in confidence such reconstruction would have given pure mathematical arguments. IOW, we would have to invent *another* statistical model without any kind of actual empirical feedback to know if such a model has anything to do with actual reality.

        Given the huge divergence displayed post 1960, I’d qualitatively guess that such uncertainty band would just turn the entire reconstruction completely useless, that is, statistically insignificant.

        Oh, wait, MBH already was (Amman and Wahl / McIntyre).

        Regarding your second point, McIntyre et al deserve some credit, but it strains credulity to think…

        I’ll concede that point easily, it’s an unproductive line of thought to ponder and speculate exactly what would have happened if X and Y, specially regarding motives. My posts regarding this issue are pretty colored by my personal distaste for the characters in question, so take them with a lot of salt ;).

      • “… it destroys the credibility of the whole reconstruction.”

        And of every other reconstruction based on that methodology.

        And of any work on any topic performed by those that hid the divergence, and of those that wave hands even now to dismiss its importance and excuse the unscientific cover-up.

        They cannot be trusted.

    • “The divergent data post-1960 fits into the category of less-reliable data,” Huh? This implies the data is *more* reliable elsewhere in the reconstruction (that in the period with presumably the BEST measurement data available). To this paleoclimate layperson this statement seems odd.

    • “continue to see nothing wrong with using a summary graph, intended for a broader audience, to show only that segment of data with which the scientists have confidence”

      If it doesn’t mislead…

  11. It is worth noting that the Muir-Russell review was very critical on this. Even though the reviews went to great lengths not to look to closely at any of the issues, even they felt they couldn’t ignore this elephant in the room:

    On the allegation that the references in a specific e-mail to a “trick” and to “hide the decline”n respect of a 1999 WMO report figure show evidence of intent to paint a misleading picture, we find that, given its subsequent iconic significance (not least the use of a similar figure in the IPCC Third Assessment Report), the figure supplied for the WMO Report was misleading.

    Evidence of intent to paint a misleading picture – you bet. And so was the RealClimate summary of the trick. They paint a misleading picture by pretending it was the overlay of the instrumental record, rather than a splice. Compounding misleading graphs with misleading blog posts.

  12. “The question I am asking myself is what is my role as a scientist in challenging misuses of science (as per Beddington’s challenge)? Why or why not should I personally get involved in this? Is hiding the decline dishonest and/or bad science?”

    Yes, it is dishonest and bad science!

    You are doing the right thing.

  13. McIntyre discussion of the Chris Folland and related climate emails does not pinpoint the fact that ‘hide the decline’ was not the point under discussion.

    The decline was hidden, almost without discussion, when Tim Osborn, acting on behalf of Briffa did not include the last few decades when he sent data to Michael Mann

    In any case, Mann as lead author, holds responsibility for how the chapter turned out.

    • Yes, responsibility for Mann, but also, I would have thought, for the 2 ‘co-ordinating lead authors’ of TAR Chapter 2: C.K.Folland and T.R.Karl, whose job it was to oversee the contributions of the various lead authors including the relatively inexperienced Mann. They failed however to give sufficiently close attention to Fig.2.20 (Mann et al’s suspect hockey stick), even though towards the end of the editing process they would almost certainly have been aware that Fig 2.20 was to be given enhanced – indeed iconic – prominence as Fig 1 on page 3 of the TAR Summary for Policymakers. Folland and Karl must share some responsibility for the promotion of this misleading diagram.

  14. JC: “I’m more interested in the handle than the blade of the hockey stick.”

    Indeed, this is the whole crux of the issue, the reason MBH98 – and all the other papers with dodgy PCAs – were undertaken in the first place, the reason they have become so central to the AGW debate and the reason they are still being defended, with increasing desperation, to this day.

    If a paper can successfully “disappear” the MWP then the claim that modern warming is unusual becomes much more reasonable. To this extent, the “hide the decline” debacle is a bit of a sideshow, although it was incredibly significant in drawing political attention to the problems with peer review, especially in relation to the hockey team….. oh yeah, plus the fact that it was incredibly dishonest, unconscionable and has cost the economies of the western world untold billions already.

  15. A wee reminder of a possibly related posting in the infamous SA article on Judith:
    “Iconoclast” posts the following:

    14. Iconoclast 05:06 PM 10/23/10

    The proposition that the average temperature of the earth’s surface is warming because of increased emissions of human-produced greenhouse gases cannot be tested by any known scientific procedure

    It is impossible to position temperature sensors randomly over the earth’s surface (including the 71% of ocean, and all the deserts, forests, and icecaps) and maintain it in constant condition long enough to tell if any average is increasing. Even if this were done the difference between the temperature during day and night is so great that no rational aveage can be derived.

    Measurements at weather stations are quite unsuitable since they are not positioned representatively and they only measure maximum and minimum once a day, from which no average can be derived. They also constantly change in number, location and surroundings. Recent studies show that most of the current stations are unable to measure temperature to better than a degree or two

    The assumptions of climate models are absurd. They assume the earth is flat, that the sun shines with equal intensity day and night, and the earth is in equilibrium, with the energy received equal to that emitted.

    Half of the time there is no sun, where the temperature regime is quite different from the day.

    No part of the earth ever is in energy equilibrium, neither is there any evidence of an overall “balance”.

    It is unsurprising that such models are incapable of predicting any future climate behaviour, even if this could be measured satisfactorily.

    There are no representative measurements of the concentration of atmospheric csrbon dioxide over any land surface, where “greenhouse warming” is supposed to happen.

    After twenty years of study, and as expert reviewer to the IPCC from the very beginning , I can only conclude that the whole affair is a gigantic fraud.

    [slightly edited for typos and punctuation]
    It seems that apparently deliberate overlooking of data problems is endemic within the IPCC process, not just the Hokey Team.

  16. I see four separate issues involved in this problem, which if conflated, can result in misleading conclusions.

    1. Did the IPCC and the authors involved transgress the boundaries of scientific probity?

    2. Did their actions lead to false conclusions about Northern Hemisphere temperatures over the past millennium?

    3. If it did, would this fact significantly alter our conclusions about anthropogenic contributions to current climate change”

    4. Are any transgressions evidence that climate science is disproportionately involved in improper conduct and is less trustworthy than other scientific fields?

    Briefly, I would answer the questions as Yes, No, No, and No.
    In slightly more detail:

    1. It may be true that the divergence problem was discussed in the literature, but that does not justify concealing the data in presentations destined for a large scientific and lay audience. Even if it is reasonable to conclude that only 20th century data suffer from such a problem (and I’m not convinced we can conclude that), this is something that readers should have been permitted to judge for themselves.

    2. There are now numerous studies demonstrating approximately the same conclusions as MBH – current NH warming probably exceeds NH warming any time during the past thousand years, even though this conclusion should be considered tentative. Interestingly, one more addition to the list is described in the March issue of Scientific American by Julian Sachs and Conor Myhrvold, who discuss (with references) evidence that the ITCZ has been moving northward during the millennium as the NH has warmed more than the SH, and is higher now than during the MWP, with a consequent threat of drought to many agriculturally fertile areas in lower to mid-NH latitudes.

    3. The MBH reconstructions tell us little about response to anthropogenic greenhouse gas emissions. Climate responds to many internal and external factors, and understanding how it varied 1000 years ago informs us about factors that might have operated then (and perhaps about climate sensitivity in general), but little about the current mix of factors. More important, a few tenths of a degree C one way or the other are trivial compared with temperature variations throughout the Earth’s history that have deviated more than 10 C in either direction from more moderate temperatures.

    4. This gets to the heart of implications from the “hide the decline” controversy, because one of those implications is that climate science is disproportionately prone to inappropriate and misleading presentation of data in comparison with other sciences that have performed well over the course of centuries. Some of this has been discussed in other threads. As someone familiar with another discipline, biomedical science, which has been responsible for enormous advances in recent centuries leading to profound human benefit, I can say that transgressions in that field have been as serious and detrimental to public trust as anything in climate science. Examples from other areas of physics were also cited by others in a recent thread. This does not justify improper scientific conduct, or course, but neither does it justify a lower trust level in climatology than in other scientific disciplines that have performed well despite the lapses over the course of many decades. Judging any person or any group requires a balanced assessment of virtues and faults, with neither elevated to disproportionate status. The latter phenomenon tends to reflect the effect of political polarization, with its own contribution to the creation of false impressions.

    • Fred, my answers to your questions 1, 2, 3 are yes, yes, yes.

      • Could you elaborate, with evidence and relevant references?

      • Of course not. They are not needed in ‘blog science’ (see above).

      • Many refs in my previous posts; will address these points in more detail, possibly in a Part II to this post.

      • Gavin 1
        Judy 0

      • Gavin -10
        Judith 10

      • Sorry, you have it wrong. Using a little known “trick”, gavin has spliced the actual record—the evidence clearly leveled that shows (from SteveMc) gavin et al are disengenuous misinformation spreaders (normally called a liars)—with a proxy based on respondents at rc.
        Original graph would have shown gavin down by 50 points, but the splice now shows him leading JudithC by a hundred.
        Nice hide the decline gavin!!!

      • Judith Curry.

        It appears to me that you obviously disagree with the recontruction, or you would not have started this thread.

        Can you post data describing a trajectory that you believe represents the warming in the last one thousand years, as you accept it?

      • Aka “can you chase after my red herring?”

        Mark

      • aka “You say that my Unicorn is a horse with a fake horn – please produce a better Unicorn. Otherwise, mine is a real Unicorn.”

      • This isn’t a reasonable question. It’s entirely possible to take issue with an approach without having a complete alternative, or indeed any alternative at all. The issue here isn’t that of preferring one paper over another, it’s of taking exception to a particular method.

      • Bernard, the point is that I don’t know, and I don’t think anyone else does with any significant confidence.

      • @JudithCurry,

        I cannot believe you are resorting to the “we don’t know” position.

        After all this time and all this good science, “we” know a good deal.

        Plus, retreating to the “we don’t know” corner is way too generalised.

        First, not all of us “don’t know”. Some of us know a great deal.

        And secondly, there are some things that are very well known indeed, and we know what the unknowns are (in category terms) – we just don’t know how big all of them are (in quantity terms).

        Your argument is not robust, from my point of view.

        You could be accused of hiding the decline in uncertainty.

      • If you “know” what the global climate looked like 1000 years ago, please tell me about it, in a way that might convince me.

      • Nobody can know exactly, for sure, 100%, what the entire, global climate looked like 1,000 years ago. Being macro-scale multicellular life we cannot travel back in time to measure it.

        There is considerably more data as time goes by, and this is whittling down doubts about some of the regional and global modelling. Ice cores clarify, but only part of the picture. Sediment cores add detail, but only some of the story.

        But exactly what the global climate was like 1,000 years ago is not the “key statistic”. To lock into a view of the world that focuses on an absence of knowledge makes the situation feel uncertain. Anybody can claim whatever they like where there is a gap in the data. We weren’t there and no cameras (or thermometers) were recording.

        However, and this is the big however, we can know a great deal about trends in climate over many timescales. I have recently tried to summarise some of the science about this. Since the beginning of the world, at all timescales, the surface of the Earth has been generally cooling down, apart from the last 150 years, when it has been warming up.

        Whether or not some city in Europe, or even a small country, or even a large part of the north Northern Hemisphere, during one season or several 100 years, around 1,000 years ago, was warmer than today’s global average really doesn’t matter in the grand scheme of things.

        What matters are the trends :-

        http://www.joabbess.com/2011/01/25/revealing-the-global-warming-signal/

        However, there is still plenty of evidence mounting that the Hockey Stick view of the last 1,000 years is correct. Mini Hockey Sticks keep turning up all over the place. In this month’s Scientific American magazine for example :-

        http://www.scientificamerican.com/article.cfm?id=a-shifting-band-of-rain

        I think that you need to step back and review the evidence from the wide variety of sources that strongly suggest, even with missing data, that the trends of the last 150 years are genuinely anomalous for time periods several orders of magnitudes larger.

        The uptick is there, and only an imbalance in the carbon cycle can explain it.

      • Jo, “Only an imbalance in the carbon cycle can explain it”. Oh really ! What an absolute poverty of the imagination. Have you considered that the conditions prior to your 150 year period were equally anamolous ? You are also absolutely sold on the idea that past variations were only regional, or northern hemispherical at best, what foolishness ! Try searching for records from the Southern Hemisphere, South Africa, Australia, New Zealand, plenty of “merely regional” variation there, and oddly in synch with the northern hemisphere. Pity about the bias.

      • John Carpenter

        “The uptick is there, and only an imbalance in the carbon cycle can explain it.”

        of course that has to be THE ONLY reason possible, isn’t it?

      • Isn’t the uptick of 0.8C in the only time we have a global record within natural bounds of variability? If not, how do we know that, given the lack of a reliable global record outside those times? And how on Earth do you ascribe it to a single forcing agent?

      • Watch our Judith, Jo might send you a harshly worded email, thus forcing you to amend a climate article on the BBC :0)

        Regards

        Mailman

      • jo,

        I think you need to review what the scientific process is all about. Of course “we don’t know” is a perfectly acceptable answer when the data don’t support the hypothesis. Just because you don’t have an alternate hypothesis doesn’t mean you have to continue to accept an unproven one.

        I am so tired of hearing this kind of reaction from the believers.

      • You could consider one of these two:
        http://www.vukcevic.talktalk.net/LL.htm
        Loehle’s appear to be favoured by the ‘geomagnetic correlation’, but that is another story I am working on (pseudo-science ?).

      • Paul in Sweden

        Perhaps congressional investigations will turn up additional and current material. It boggles the mind that after climategate full and complete investigations on both sides of the pond were not launched.

        If there were a similar whistleblower event involving the Nuclear, Oil, Banking, Pharmaceutical Industries, etc.. the leaked documents would not have been the limit of scope of submitted evidence. Why were the rest of the undisclosed emails and documents not investigated?

        It is not just the decline that has been hidden.

      • “Perhaps congressional investigations will turn up additional and current material.”

        Hammer will meet anvil and then we will see.

      • The way that the hearings were conducted were atrocious. It was the equivalent of the defence conducting the defence and the prosecution case in front of a judge and jury of the defendant’s closest friends with the defendant being allowed to decide what evidence is presented to the court and what evidence was withheld.

        We have not yet seen an independent analysis of the standard of ‘climate science.’ We have seen lots of allegations and snippets of evidence of grotesquely misleading, cherry-picked, bullying tactics aimed at confirming a narrative in support of a political agenda, that flout the age old tenets of the scientific method.

        If ‘climate science’ has nothing to hide, and the “hockey stick team” are clean, scientific and above board, then they have nothing to fear from a truly independent investigation.

        I look forward to the day when such an investigation, without fear or favour, looks utterly independently at all the papers, on all sides, and investigates fully the science and only the science, convenes and concludes, whatever that conclusion may be. So long as they are investigating in a search for objective truth and adherence to ALL of the scientific method, then whatever such an investigation concludes, I will accept.

        There has been far too much revealed so far that calls into question the impartiality of the Hockey stick team. Many other scientific disciplines have peer-reviewed and documented solid evidence of a warmer medieval warm period in many locations around the earth. Using “dodgy” graphs to dispute accepted and extensively documented historical, geological, anthropological, botanic records showing warmer historical events is dishonest. To use tree-rings (which cannot be used as a reliable temperature proxy AT ALL) to try to contradict such overwhelming prior evidence of a warmer past is utterly ridiculous and completely laughable. Or it would be laughable, except for the call for trillions of dollars worth of political policy to strangle human endeavour and requiring a global return to the stone age if the more alarmist end of the AGW crowd are to be believed.

        There is ample evidence in other fields that we are NOT at the warmest point in 1000 years.

      • Dave Dardinger

        “2. There are now numerous studies demonstrating approximately the same conclusions as MBH – current NH warming probably exceeds NH warming any time during the past thousand years, even though this conclusion should be considered tentative. ”

        Every one of these additional studies use some permutation of the same questionable proxies. (Plus window dressing) Frankly I can’t believe the warmers here aren’t aware of this fact. This makes me doubt their scientific honesty. If you really insist I give a link to one or more lists of the proxies used in the other multi-proxy temperature reconstructions, I can do it, but you’d be much better off to go directly to Climate Audit and click on one of the topics in the left margin near the top that refer to a particular reconstruction and read up on it.

      • I hope I’m not presumptuous, Judy, but I sense that your disapproval of the particular actions you discuss is distorting your objectivity. I believe lapses from the ideal should be put in perspective, both in terms of their seriousness and their implications for our interpretation of scientific evidence. I may not agree with Gavin that the lapses were inconsequential (certainly they had political consequences), but neither do I see them as overwhelming, nor do I believe they change our view of climate change in any appreciable way.

        (For some reason, my login above failed to cite an active URL, but this has been corrected).

      • Fred, I will do a part ii on “why this matters”. it DOES matter.

      • You have our attention. Maybe it should be a guest post at WUWT.

      • Yes it should Theo. And on climate audit. And at the Heartland Institute. And then Fox News. And Finally, the pinnacle…Professor Glenn Beck!

        Maybe go around and give the Koch Brothers a private briefing as well. they’d love it…

      • FWIW, very few of these institutions/people have any relevance/traction outside North America. No point on telling UK based or Oz based or EU based or NZ based about them, since they evoke nothing to us.

        This is supposed to be *Global* warming.

      • WUWT has a massive UK following, FOX news is available in the UK but is thought of as a very very poor and unreliable media platform, Glenn Beck has a small following of right wingers.

      • Sure – WUWT has a worldwide following.

        But Fox News isn’t available to me here in Surrey Freeview afaik and I still don’t know who Glenn Beck is. Is she like Oprah?

        Whether one or two follow their work does not negate the point that they are unknown to all intents and purposes.

        Sure – WUWT has a worldwide following.

      • Latimer,

        I like to think of Fox News as the anti-BBC :)

        Besides, those numbers dont lie, Fox News continues to be America’s most trusted media outlet…more trusted than all the alphabet mfm put together.

        Regards

        Mailman

      • If Anthony doesn’t post it there, I will.

      • Judith,

        Based on your stark criticism of paleoclimatology, I can understand you answering yes to Fred’s questions 1 and 2, but to 3? How does attribution of recent climate change depend on temp reconstructions from the past 1000 years?

      • quick reply: too much reliance on interpreting all of the recent variability as forced, where multidecadal internal variability is probably much more important than ch 9 of AR4 says. this overreliance is justified in part by climate models being compared with a relatively flat time series for the last millennia. Note: this refers to the stick, not the blade; it is the stick that is important.

      • A climate that can by itself (ie without being forced) wonder off quite far in any direction would be a very sensitive and unstable climate.

        Moreover, the temp cannot wonder off all that far in any one direction without being pushed back to its equilibrium value because of the ensuing energy imbalance (unless the temp shift is due to shifting of energy around between its subsystem).
        (http://ourchangingclimate.wordpress.com/2010/03/08/is-the-increase-in-global-average-temperature-just-a-random-walk/ )

        Your argument seems to rest on two factors:
        – Attribution is based on knowing the amount of natural variability
        – The baseline for the amount of natural variability is based on the climate over the past milennium

        This would be an interesting topic for a technical thread (ie without the accusatory tone).

        The first one makes sense, though I was under the impression that parts of the instrumental period without strong net forcing were also used as a baseline for the amount of expected natural variability?
        Over the past milennium there were also natural forcings at work. Wouldn’t a greater response to those forcings imply a greater climate sensitivity?
        Doesn’t attribution depend more on matching specific patterns of the observed with the expected warming, rather than on past climate variability/response (where the distinction between what is forced and what is variability is far from clear)?

      • Bart, re your last paragraph, this was discussed extensively on my previous detection and attribution threads. Given the large uncertainty particularly in solar and aerosol forcing, not to mention handling their indirect effects in the models, explanations of the parts of the record prior to 1970 that involve solar and or aerosol forcing are unconvincing. And if natural internal variability played an important role in the early part of the century, why would we assume that it didn’t play an important part in the later part of the century? the peak warmth near the end of the century got a significant boost from warm AMO plus warm PDO; I do not think that the CMIP3 runs did a convincing job of separating this kind of variability from forced variations. The CMIP5 decadal simulations, combined with the century scale simulations, could provide some insights here.

      • I believe Bart is correct. Not to belabor the point, but global temperature has moved up or down by 10C or more over the course of geologic history. A few tenths of a degree variation in NH temperature during the MWP is rather minor for concluding that major re-evaluation of current warming is warranted. That would be true even if we had precise knowledge of the internal and external climate drivers operating 1000 years ago. We don’t.

        Current attribution requires an accurate assessment of the current mix of climate drivers- it’s a 20th-21st century problem, not a MWP problem. If the drivers operating a millennium ago produced slightly greater temperature changes than estimated by MBH, it implies that climate sensitivity is slightly higher than we have thought it to be. This would apply to both anthropogenic and natural factors, and so the balance would be unlikely to change much. I don’t suggest that better knowledge of the MWP would be worthless, but it would have very little effect on our understanding of the causes of the past century’s warming.

        The above assumes that the MBH conclusions were inaccurate to the extent claimed by a number of critics who have assessed the paleoclimatologic data. However, in my earlier comment, I also cited one example (the ITCZ) of evidence that the conclusions were probably largely correct after all, despite statistical errors and despite the failure of the IPCC to cite evidence of the divergence problem. I believe Gavin Schmidt has cited others, and readers can find still more in the literature. To me, the issue is much less one of science than of public relations , and for the latter, some IPCC authors can certainly blame themselves, even if their fiercest critics have magnified the nature of the infractions.

      • A few tenths of a degree variation in NH temperature during the MWP is rather minor for concluding that major re-evaluation of current warming is warranted.

        Fred –
        What evidence do you have that the NH temps varied by tenths of a degree? Or that the temp variation was confined to the NH? These are assertions by those for whom any other interpretation would be inconvenient, but they’re not supported by archaeological evidence. Nor by a wide range of paleo evidence. Either read some archaeology or go to the Idso site – preferably both.

      • Well, a few tenths of a degree variation in modern temperatures is rather minor for concluding that major re-evaluation of current energy use is warranted.

      • Highly sensitive to what?
        It has been remarkably boring these last ~150 years of steadily increasing CO2.

      • There seems to be a problem of what we might call ‘hermeticism’, ie a small group of scientist who are prepared to discuss among themselves their ‘secret’ knowledge of uncertainties but, when they exit the ‘cave of knowing’ they become purely political and ‘appear’ to abuse the scientific process. Ie a dichotomy that doesn’t completely condemn them as scientists but, rather, as conveyors of that science.

        PS I couldn’t help wanting to quote a poem of mine after your reply to ‘fredmoolten’, which you can excise as you see fit:

        It was a comic sight:
        His earnest face forward
        In the fury of impotence,
        Awkward and shyly expressed,
        And she agile in her agreements
        Reassurance with a “Yes, yes, yes.”

    • “4. Are any transgressions evidence that climate science is disproportionately involved in improper conduct and is less trustworthy than other scientific fields?”

      Irrelevant. Other fields are irrelevant. The issue is this field and its improper conduct!.

      • Edim – It’s not irrelevant for the reasons I mentioned. A scientific discipline deserves to be judged by its overall performance. If other fields have made major advances despite lapses equal or worse than those discussed here, it’s reasonable to conclude that climate science is capable of the same and deserves equal trust. I would argue that it probably has met that standared, but of course, that requires a discussion well beyond the limits of this thread concerning the positive contributions.

      • There are sceptics who are also sceptical of other fields (tip of the icberg), but this just muddies the waters for this discussion.

        There is scientific method, no need to include other fields for comparison.

      • Trust? Trust in science is irrelevant except when policy issues come up. As for medical research, here too there are large mine fields – the risk of having everything look right and being wrong in reality is pretty high, so I take all these with a grain of salt. Over time, if enough work is done by enough researchers I can develop some confidence in them.

      • ‘Trust in science is irrelevant’.

        Stuff and nonsense!

        Surely the whole basis for science’s relatively high status in society is that the general public trust scientists to be objective and to act with integrity.

        And because, if carried out with those characteristics, it is an extraordinarily useful way of understanding the world.

        Done otherwise, however, it is of no more utility than a Dan Brown book, and probably far less entertaining. Retaining trust is essential. Which is why betraying it is considered to be such a serious matter…as this thread amply demonstrates.

        If you believe that acting in an untrustworthy manner is compatible with/irrelevant to work as a scientist, remind me never to bother with any conclusions you might draw.

      • Latimer-

        Yes, when it comes to broad public interaction trust comes into play. I also view this as perception of integrity. In science, I expect the work to be well checked, so unintentional errors and intentional errors are corrected.


        If you believe that acting in an untrustworthy manner is compatible with/irrelevant to work as a scientist, remind me never to bother with any conclusions you might draw.

        No, I think that trust should be excluded from the scientific process as much as possible. I’m retired from the research side of the semiconductor industry, but I still consult in nanotechnology if something interests me. From the research side, a “package” of documentation results is produced. The usual requirements aren’t difficult to meet. The package I produce goes way beyond what is normal industry standards. All experimental samples are indexed and stored (where possible), so if someone wants to repeat the measurements they can, if they have a new measurement technique in the fiture they can compare to the techniques which was used. If they later think there may be something else important that wasn’t measured, it can be measured. Continuity from the research effort is maintained. All details of metrology is documented, so the results can be duplicated by purchasing the same equipment and following the measurement procedures (this is in theory; some metrology is just difficult). The details of how and why the experiments were designed and run is indexed and kept. All raw data, meta data, any data scrubbing (I include all data in the analysis except for any data points which can be conclusively shown to have a problem due to a specific reason. Even here, I may keep it in. It’s documented either way), the analysis (including code and meta data where applicable, and on and on. Everything is indexed for easy retrieval in the future. Any limitations specific to the work are explicitly noted up front. My preferred research report format (and hee I’m referring to individual experiments, not the overall research program) lists conclusions, then recommendations, then the details of the experiment and analysis. This makes it natural for others to read the report critically, making sure the recommendations follow from the conclusions, and the conclusions are tightly supported by the research. I’ve seen many conclusions by other which contain some elements of speculation, which I don’t do. Back when data consisted of a printout, a hard copy of the data would be attached, or the data indexed in a master file, and referenced in the report. You didn’t have to trust me, you could easily check what I said.

        I’ve been in the position of checking other people’s work. For several years, all I did was find out where others went wrong, and then find a solution. This gained me an appreciation for organizing and documenting beyond what was required of me – I put out the information which would make it easy to find where I went wrong and why, or look for other things that weren’t anticipated. I also found that doing this made it easy for me to find my own mistakes before the research reports were public within the company.

        These days, most of the details can be put on a shared network drive, and I keep as much as possible on a flash stick on my person. If any question arises, it can be answered in an level of detail needed any where a PC is available. Before this, I had to assemble copier paper boxes of all this and take them to meetings. I someone thought the data said something other than what I claimed it said, I could spread the printouts in question down the conference table, show them where my interpretation came form, and give them a chance to either challenge or capitulate. When you’re dealing with VP level scientists, it’s the only successful way I’ve found of keeping from being derailed.

        There’s more, but in general I don’t think you’d be unhappy with any of my research output. Maximum transparency, maximum future utility of the research.

      • OOPS! forgive the typos

      • Wrong A scientific discipline needs to be judged in accordance to the extent to which its practitioners seek to overturn the world order. Those who study butterfly mating tendencies do not have to meet the same standards of rigor as those who seek to deprive billions of people of their lives, liberty and property.

    • On Fred’s #1. In hindsight the issue might well have been handled differently. But was that really obvious at the time? “Scientific probity means that may be only maintained, what is proven and can be proven. “

    • On Fred’s #1. In hindsight the issue might well have been handled differently. But was that really obvious at the time? “Scientific probity means that may be only maintained, what is proven and can be proven. “ Proven is too strong for the empirical sciences so let’s say “strong evidence for”. The authors felt they had this in their references. So, while better judgments could have been made (say by adding a note to the graph) it is not clear scientific probity was violated. How best to present evidence to a lay audience is a matter of judgment. You don’t want to get so detailed that their “eyes glaze over.”

      • Mike, you’ve inadvertently identified the key issue. There is no “strong evidence for” anything in the post-1960 climate that explains the divergence problem … at least, nothing that is unique to the modern era. The proxies diverge from temperatures post-1960. This could lead one to the conclusion that proxy data could have easily diverged from temp in the distant past, too. In order to avoid such a conclusion, the divergent data was removed from the IPCC graph; as you say, based on their “references.”

        BUT … the evidence from these references was nothing more than speculative hypothesizing … which you can see for yourself in the original papers. That is, the “references” that you presume show “evidence” for removing divergent data do nothing of the kind … they simply state speculation. The only empirical basis for removing the divergence from the graph was the authors’ belief that it wasn’t supposed to diverge.

    • Briefly,
      1. agreed

      2. http://judithcurry.com/2011/02/22/hiding-the-decline/#comment-45924

      One of the papers own authors doesn’t believe in the veracity of the paper’s assertions. Yes, their have been numerous papers, all suffering from the same difficulties. I know of none that have survived the statistician’s scrutiny.
      “with a consequent threat of drought to many agriculturally fertile areas in lower to mid-NH latitudes.”
      Strange, I thought the alarmists just got through saying more precipitation would be expected in a warmer climate. (Personally, I don’t think they have a clue as to which climate disaster will happen nor where.)

      3. You are confusing “your conclusions” with “our conclusions”. As illustrated by this discussion, many people respond better to graphics as opposed to data and discussion. Perhaps I’m missing the framing of the question, but for climatologists and people current on the issues, you’re correct, no it doesn’t significantly change anything regarding our current mix. Mainly because no one(current and interested) puts much validity to the graph. We know the blade is wrong. We know the handle doesn’t properly represent the past, too. Of course, there should be that bothersome explanation about the LIA and MWP and why we know these things aren’t occurring now. To the policy makers, this is an entirely different issue. They see a single line on graph in the shape of a hockey-stick. That’s the end of the story.

      4. “This does not justify improper scientific conduct, or course, but neither does it justify a lower trust level in climatology than in other scientific disciplines that have performed well despite the lapses over the course of many decades.”

      No, I put climatology just slightly lower than biomed and many other fields. “Performed well” is quite subjective. How about ‘Society has managed to advance in spite many short comings of various scientific fields. They could have easily and significantly performed better with an insistence of possessing of a modicum of compunction.’?
      Sorry, I don’t buy into the “everybody does it” argument.

      Sorry for the length, I tried to be brief, I hope I didn’t come off as short.

    • Fred Moolten ,
      You argue that there have been similar errors/frauds in other fields, and
      that therefore climatology should not be seen as particularly suspect.

      But how many of these these other incidents been funded by a single party, that has outspent all others by a factor of perhaps 5000, and that has a vested interest in the flawed outcome being believed? And in any such examples, has there also been a complete lack of contrition?

      And as to your lamenting political polarization, what we have in this case is politically funded science being distorted so as to support further politicisation of society. What other outcome can one reasonably expect?

    • Fred –
      I will attempt to answer your questions and give brief reasoning for each of my answers.

      1. Yes. Whether the intent was to mislead or just paint a nice tidy picture, the fact is the graphic did mislead many other scientists and lay people into a false degreee of certainty as to the unprecedented nature of recent warming.

      2. Yes. Whether or not subsequent work appears to support (more or less) the earlier reconstructions, at the time, the action lead to false conclusions as to the degree of certainty that could be placed on the accuracy of the reconstructions. Some may argue that the divergence issue is well discussed in the specific literature, but the issue as I see it is the degree of certainty that other scientists, policy makers, and lay people would conclude from the graphics.

      3. A qualified yes. Of course, the reconstructions tell us nothing about the role of CO2 emissions (or land use changes or other pollutant emissions and discharges) in affecting climate, but as I see it, it goes to the certainty issue again. With a higher than deserved degree of certainty in the reconstructions, it allowed climate scientist to potentially discount role of natural variability. This leads to a higher than deserved level of certainty in the conclusion that most of the warming in the last half of the 20th is due to anthropogenic GHG emissions.

      4. an unqualified and emphatic NO. What many who rail against all of climate science forget is this was an action of just a very few individuals and the strident defense of it is made mostly by those involved or their close associates or blog denizens. I think the fact that most climate scientists haven’t actively spoken out against it is not atypical of any scientific discipline where such an issue occurs.

      • Agreed on all, particularly number 4.

      • Climate science isn’t like any other scienctific discipline. When science is used fraudulently or incompetently to deprive people of lives, liberty and property, what moral obligation lies with those who have the knowledge and authority to stop the fraud, yet choose to remain silent?

        When the stakes are this high, moral duty increases commensurately.

  17. Craig Goodrich

    The difficulties I have with “dendroclimatology” in the first place are:

    a) The effects of climate change on local precipitation vary widely. For example, the MWP provided sufficient precipitation in Europe, Japan, and northern China for crops to take advantage of the longer growing season, but caused severe drought in the American southwest. Thus if I pretend growth is directly related to temperature, and average the poor growth of treese in the southwest with good growth in Europe, I get a flat line. There are too many confounding variables here.

    b) Paleoclimatology inherently involves extensive statistical manipulation of proxies. But dendroclimatology adds to that a host of preliminary manipulations to relate ring width to temperature and discount other factors affecting growth, leading to a situation where the final product has been so thoroughly mashed that it resembles the actual data about as much as baby food resembles steak. The opportunity for tendentious hacking is enormous.

    Thus I would put much more faith, even a priori, in a study like Loehle’s, which purposely and specifically excluded tree ring data.

    • Craig

      We don’t even have to get into the specific problems with dendrochronology. The divergence between tree rings and observations after 1960 demonstrates that tree rings are not reliable air temperature proxies, and this should have stopped publication of the MBH results. The fact that it didn’t is where the scientific malfeasance came in.

  18. The day hasn’t come yet, when I will be lectured about “honesty” by the guy who had to be dragged kicking and screaming into acknowledging McIntyre’s contributions in the identification of the BAS station data errors, just two years ago (see “Prometheus”, post 4936).

    Anyway…Judith – your hopes about getting “a useful analysis and assessment of the paleodata for the last millennium” might rightly be very low. Remember what Lord Oxburgh said, during one of the hearings by the UK Parliament’s Science and Technology Committee:

    Q36 Graham Stringer: Did Professor Jones say, when he was in the discussions, that it was actually impossible to reconstruct temperatures over the last thousand years?

    Lord Oxburgh: I don’t believe he said it, but it probably would have been true. Well, it depends what you mean by “reconstruct temperature over the last thousand years.” I mean, the whole concept of a global temperature is actually a very subtle one. How do you decide what the temperature of the globe is? We know that all sorts of local circumstances associated with local weather are giving all sorts of small-scale variations. We know that most of the observations until the last century were based on land. Most of the land is in the northern hemisphere, so you had relatively few observations in the greater part of the surface. So actually deciding what a global temperature is is pretty darned difficult. You may be able to track temperature at a particular area, but how that relates to others is much more difficult.

    I am fairly convinced by the work of Jones himself, which is based largely on instrumentation and instrumental records over the last 150 years, something of that kind. I think the instrumental records give us the best kind there are. Then what you have got to do with those instrumental records, which are not distributed geographically, as you would really like, is to interpolate between them. You’ve got to then make extrapolations to the areas that you can’t get to. So it is a pretty difficult business. That is why on the serious publications massive uncertainty bands are associated with temperature reconstructions.

  19. Gavin, If the IPCC had any integrity at all they would have thrown out the hockey stick and used other examples of a “cooleth” MWP. There must be tons of it in the published articles. If there was not much else to use then this tells me the IPCC was desperate to get there idealogy presented.

  20. Deep Climate already demonstrated how McIntyre constructed his case from out of context quotes. It is disappointing to see that Judith Curry failed to do due diligence on her post.

    • Terrific. Does this mean that there is no divergence problem and that the data after 1960 were actually included in the plots under discussion? And that there was no splicing with instrumental data?

      • I thnk it means you are great at reading headlines but not reading the actual reports. Just like Muller.

      • This is non-responsive. If you didn’t think that McIntyre’s misrepresentations were relevant, why did you include them in your post?

      • Judith Curry.

        It is quite apparent that you obviously disagree with the recontruction, or you would not have started this thread.

        Can you post data describing a trajectory that you believe represents the warming in the last one thousand years, as you accept it?

      • I’m not sure if it follows that if you disagree with someone’s assertion of a specific trajectory, that you must have an alternative trajectory you believe is true.

        You could simply believe that the answer is not known, or is unknowable.

      • What a convenient lack of curiosity..

      • Or a convenient understanding of the limitations of reality :)

        Being curious doesn’t require one to have a specific dogma.

      • Did you even read your link? You must be joking.

      • Bruce Cunningham

        “Terrific. Does this mean that there is no divergence problem and that the data after 1960 were actually included in the plots under discussion? And that there was no splicing with instrumental data?”

        That is the title of the post, and seems to be something that Gavin and his minions try and not answer directly. Instead they put forth one red herring after another trying to obscure the fact that the diverging part of the data was deliberately deleted from the graph. They actually explained why they did it! They did it to “hide the decline”. Everyone knows why, even Gavin and Co. The fact that he continues to pretend he doesn’t says volumes about him and many others.

        It is great that you have addressed this issue Judy. My opinion is much the same as this fellow from Oxford.

        http://bishophill.squarespace.com/blog/2011/2/23/the-beddington-challenge.html?lastPage=true#comment12009168

        You make me proud to be a Ga Tech graduate, unlike Jen above! Keep their feet to the fire!

    • Tim? The “hide the decline” was bad science. How does McIntyre quoting “out of context” anything, have anything to do with this case of bad science? Would you like to do an in depth peer review of some of the more recent proxy reconstructions?

    • Balderdash! Scrupulously honest scientists would have published that they had collected forty years of data that undermined the reliability of tree ring data. They would have dropped all of the tree ring data from their evidence.

      • “Scrupulously honest…..”

        Not only are these traits not required for climatologists, they are, apparently, discouraged. It muddles the message.

    • the case for hide the decline has little to do with quotes, these just provide context. The hiding of the divergence (and other manipulations like end-padding and thick red lines for instrumental) are all to be seen by dissecting the graphs. Real data wonks use the data, not just word processors.

      • The material under discussion was not limited to fellow scientists. It was presented by the IPCC to the World. It must satisfy the standards of truth employed by the ordinary tax payer.

    • Judith

      Don’t be diverted by Tim’s obfuscation, misdirection and muddying the waters.

      The issue is unprecedented global warming was presented as a hockey stick to the world. In closer examination, the hockey stick was found not to be made of one material. The handle is made of tree rings, the blade of thermometer.

      Why the blade is not made of tree rings? To hide the decline.

      That is deception.

      • This, from a person demonstrably non-proficient in basic statistics…

      • Top work. When you can’t refute a statement, attack the authour. Pray tell, what was statistically incorrect in that statement?

    • Tim Lambert:
      “It is disappointing to see that Judith Curry failed to do due diligence on her post.”

      Due diligence = reading a “Deep Climate” blog post?

      LOL!

    • Tim,
      You make me sad to be an Aussie.
      Zorro

    • Tim,
      The RC rationalization is not convincing to many informed people.
      Why does your opinion that it is otherwise trump the conclusion of Dr. Curry and many other people who are at least as qualified as you to your opinion?

    • Tim Lambert :

      I’m surprised you haven’t mentioned your other source of climate science information; Gareth the New Zealand truffle farmer that you frequently link to as an important source of science analysis.

  21. I would like to add a bit of emphasis. The decline took place after 1960. During most of that time, the data was collected by scientists involved in the Climategate emails. The decline took place on their watch. The tree ring data that shows a decline in temperatures and a divergence from thermometer data is the most reliable data they have because they collected it. Surely, serious scientists or just scrupulously honest scientists would have concluded that the tree ring data is suspect as their own data collection showed. Hiding the divergence amounted to rejecting their own work. Scrupulously honest scientists would have published that they had collected forty years of data that undermined the reliability of tree ring data. They would have dropped all of the tree ring data from their evidence.

    • Theo – It would have been misleading to omit tree ring data when the latter are informative, and in fact, correlated well with measured temperature over many decades. The appropriate action is to disclose the areas of divergence, offer tentative explanations, acknowledge their limitations, and let readers judge. Simply pretending the data did not exist would have deprived readers of a source of information and would have implied that the readers were incompetent to evaluate it when given enough evidence to do so.

      • Aren’t you ignoring the importance of a scientist’s own work of data collection? I would think that after forty years of data collection, a scientist would have a highly refined critical appreciation of the older data that had been passed on to him. If it were me, I would be highly impressed by the fact that my data diverged drastically from what had been collected before me. If a young scientist has little confidence, he might criticize himself. For a scientist comfortable in his skin, the critical juices should flow and he should show no mercy as he criticized the earlier data. Criticism is no less part of science than data collection.

      • Fred,
        There is no convincing data to support the assertion that tree rings make good thermometers to the precision levels claimed by Mann, Briffa and gang.
        They hid their problem, and no amount of rationalization by you, Schmidt or from peanut gallery neverwuzzers like ianash will change that.

      • hunter, start reading some science and stop reading American Thinker. Then you’ll understand why your comments are nonsense.

      • Don’t read American Thinker.
        So far you fail on breast exams, American Thinker and your ability to post links or citations to support yourself.
        Do you in fact know how to post a link?

      • “Simply pretending the data did not exist would have deprived readers of a source of information…”

        You mean, like using a “trick” to “hide” the data that did not show what you wanted it to?

        Good thing they didn’t replace said inconvenient data with OTHER data that did show what they wanted shown. That would have been truly deceptive. Oh, wait…

      • “It would have been misleading to omit tree ring data when the latter are informative, and in fact, correlated well with measured temperature over many decades.”
        Fred, correlation is not causation. When something correlates well for some decades, and then not at all for other dedcades, the default hypothesis must be that tree rings don’t reliably reflect temperature. No other honest interpretation is possible.

      • Isn’t it true that the model was calebrated to the recorded temperatures? And that the model fitted closely to the temperatures ecept for the post 1960 period? It seems to me that the model should fit closely to the calebration data, else you’d keep working on the model till it did. The fit over this period is not evidence of correct proceedure.

    • “I would like to add a bit of emphasis. The decline took place after 1960.”

      How do you know this? The chart shows that but what of the data? You’ve seen the raw numbers?

  22. Tim,
    to my knowledge, Steve McIntyre constructed “his case” with a very careful and scholarly examination of the statistical methods applied, including very specific points about principal component analysis, the number of component to be retained, the kind of statistical test to use (and their virtues and shortcomings), the conflation of various types of data within the same chart (including some years averaged over 30-40 years and other years not averaged at all), an many other similar scientific points. I admire your capacity to be satisfied with a “demonstration” to the contrary given at Deep Climate, which I regrettably do not share. I am afraid I am not the only one, should I say. About how McIntyre “constructed his case” I cordially recommend reading The Hockey Stick Illusion. I am not recommending that you share the book’s conclusions, mind you: yous that you read it. Most of the references are to readily accessible sources such as published papers and online blogs, so you can “demonstrate” to yourself the presence or absence of “context” in any of the “cases” that were “constructed”. In fact, I remember several issues in which digging up the context made them incredibly worse.

  23. Judith, thanks for the post, it was long overdue. I share your concerns outlined in your primer but I am curious as what motivated you to say “Can anyone defend “hide the decline”? I would much prefer to be wrong in my interpretation, but I fear that I am not”. What do you prefer to be wrong about –the reputation of climate scientists generally, the honesty of Mann, Jones, Schmidt et al., or that AGW might have been overestimated?

  24. OK. Judith, if you’re going to delve into tree rings you have to do the same thing with the actual M&M analysis of the Mann paper that started this off,

    Why did M&M sequester the data with the biggest positive response?
    Why did M?&M graph their data with a Y-Axis 10 times smaller than Mann’s graph?

    The “hide the decline” graph btw was a one-0ff small time production almost on the level of a PowerPoint presentation. It wasn’t part of a big journal article. It wasn’t part of any big proof or any big misdirection play,

    If you want dishonesty, you might want to start with that characterization.

    • The issue at hand is what showed up in the IPCC reports, everything else is small potatoes. What showed up in the IPCC TAR and AR5 was misleading.

      • What’s in the IPCC AR4, so we can go over what is misleading:

        Several analyses of ring width and ring density chronologies, with otherwise well-established sensitivity to temperature, have shown that they do not emulate the general warming trend evident in instrumental temperature records over recent decades, although they do track the warming that occurred during the early part of the 20th century and they continue to maintain a good correlation with observed temperatures over the full instrumental period at the interannual time scale (Briffa et al., 2004; D’Arrigo, 2006). This ‘divergence’ is apparently restricted to some northern, high-latitude regions, but it is certainly not ubiquitous even there. In their large-scale reconstructions based on tree ring density data, Briffa et al. (2001) specifically excluded the post-1960 data in their calibration against instrumental records, to avoid biasing the estimation of the earlier reconstructions (hence they are not shown in Figure 6.10), implicitly assuming that the ‘divergence’ was a uniquely recent phenomenon, as has also been argued by Cook et al. (2004a). Others, however, argue for a breakdown in the assumed linear tree growth response to continued warming, invoking a possible threshold exceedance beyond which moisture stress now limits further growth (D’Arrigo et al., 2004). If true, this would imply a similar limit on the potential to reconstruct possible warm periods in earlier times at such sites. At this time there is no consensus on these issues (for further references see NRC, 2006) and the possibility of investigating them further is restricted by the lack of recent tree ring data at most of the sites from which tree ring data discussed in this chapter were acquired.

        D’Arrigo 2007 (post-IPCC), while much more informative than any report previous, still was unable to come to a conclusion over the causes, and it’s conclusion sounds much like the IPCC explanation. Where is the IPCC’s explanation misleading in this respect?

        This review did not yield any consistent pattern that
        could shed light on whether one possible cause of
        divergence might be more likely than others. We
        conclude that a combination of reasons may be involved
        that vary with location, species or other factors, and that
        clear identification of a sole cause for the divergence is
        probably unlikely. The studies cited herein also varied
        with method of analysis (e.g., regression, Kalman filter,
        modes of standardization) and site ecological conditions
        (e.g. latitudinal/elevational treeline or productive forest,
        coastal or interior sites). The issue is thus highly
        complex, with likely ecophysiological feedbacks coming into play related to differences in environmental
        conditions between sites, species and regions. For
        example, there have been recent shifts in patterns of
        insect infestation (G. Juday, Univ. Alaska Fairbanks,
        pers. comm. 2006), as well as forest dynamics that capreclude a purely positive response to warmer temperatures in areas of Alaska (Jacoby and D’Arrigo, 1995). In short, we believe the problem is real but that there does not appear to exist a single “divergence” phenomenon
        with an underlying causal mechanism

      • That’s an interesting concept that these trees quit due to stress when it gets too warm, explaining what happened in the 60’s. The AGW case for damage could have been made stronger with this piece of information added to the MBH paper and showing the decline in its full glory.

      • If trees are sensitive to 0.x degrees of temp average change, I have yet to see any evidence at all to support it.
        Only a lot of hand waving from those who desperately need for that to be the case.

      • That’s a great bit of hand waving. Scroll up to the top. You notice the topic? A graph. Did you include the graph? No? Well then your posting is almost relevant.

      • There’s a graph on the page. The piece I posted references the graph and describes the divergence problem. Here is a link to the page in the IPCC. And here is a link to the graph that appears on the same page.

        And we know that this paragraph references this image because it cites the image:

        Briffa et al. (2001) specifically excluded the post-1960 data in their calibration against instrumental records, to avoid biasing the estimation of the earlier reconstructions (hence they are not shown in Figure 6.10)

        I figure what the IPCC says about the graph is also part of “what showed up in the IPCC reports”. Interesting how the text that explains what’s in the graph is considered ‘hand-waving’ tho. Not sure I see logic there.

      • Because one bunch of crooks got away with a large sum of money, we should turn a blind eye to a second set with equally grandiose ambitions? Is that your point? A new take on ‘two wrongs do make a right’?

        Might make sense to you, but not to me…….

      • Something up with the postings here. This was meant as a reply to a completely different post from me old mucker grypo.

      • Ty Grypo, much better. See, now people can go look at the pretty pictures. Which is what we were talking about. The explanations to the graphs are sufficient for people engaged in the science. The graph in question is totally insufficient for the purposes of accurately conveying a finding. The justification for the graph seems to be “if after viewing the graph you came away with the view that the treeometers perfectly correlated with observed temperatures, you should have read the fine print.”

        Given that one of the purposes for the IPCC’s existence is to provide policy makers information, if find this approach disingenuous. Does anyone really believe our bureaucrats and politicians could read and understand what was written about the graph? Geez, they need a dictionary for 3 syllable words and still won’t understand the context.

      • Given that one of the purposes for the IPCC’s existence is to provide policy makers information, if find this approach disingenuous.

        How is it ‘disingenuous’? While you can argue the scientific validity of anything in the chart, attributing tags of ‘disingenuous’ and ‘dishonesty’ are merely subjective reactions, it’s especially odd to expect them to know how far to dumb it down for stupid policy makers . As has been argued many times, this is the way the scientists thought was the best way to represent the data. Post 1960 data on that particular proxy was faulty. I doubt lawmakers would appreciate faulty data being highlighted in a graph, just as they would not have appreciated not having the divergent data explained. Reasonable people can disagree on these points about science and communication, but the crux of this issue is that there is a large number of people who continue the premeditated dishonesty gambit. The logic behind these assertions is faulty. Just because something is uncertain, that does not mean it is disingenuous to show it, especially with large error bars and explanations and references to original works.

      • Well, attributing to motivations is always interpretive.

        Post 1960 data on that particular proxy was faulty.

        This is where I get a bit frustrated. The “proxy” data wasn’t faulty. The data disagreed with the narrative of the story they wished to tell with the graph. So, they removed it to convey a consistent message. I believe this to be an accurate characterization of the events.

      • No, it disagreed with the all the temperature data from all other sources. It was faulty, no questions there. Calibrating it and setting that curve to it would be faulty, as the IPCC says is the reason Briffa did not include it. It would bias the results, whether the error forced a lot more growth, or, as is the case, less growth. The data is useful in finding reasons, which is very important understanding how good tree rings are for thermometers, for example, whether or not this tree ring recon is useful beyond a certain temperature.

        Perhaps a good question to ask ourselves is what would have been done, if say, the faulty data had shown that temperatures had gone way up. And this disagreed so much with all the other proxies, (boreholes thermometers, etc) that the graph showed an unusual spike that stood out, to a confusing degree and known to be faulty. Would policy makers want to see that? Would the scientists have put it below the thermometer lines? I am betting the answers to that one will be sifted through the confirmation bias also, but it’s a worth a try, if anything, to see if we can be more objective about motivation.

      • Yes, it disagreed with data from all other temp sources including observed temps. That doesn’t make the data faulty. It calls the conclusions from the data into question. Here’s a question. Why include the study at all? The last 50 years are in disagreement. Seeing that the 1st thermometer was invented in 1714, how much of the recorded temp record can really be correlated with a tree ring? Given that calibration and distribution of thermometers didn’t happen over night.

        What was the compelling reason that made it so necessary that this be included in the IPCC? The inclusion being so important that we’d have to splice a graph together to tell the proper story, but, by God, we must have it in the report!

      • I just realized. The M&M paper is something of a Boojum, isn’t it?

        It actually doesn’t say that Mann’s code forces a hockey stick on the data. M&M have just let us take its plaintive tone and go with it. The M&M paper only says that it “often” would create a hockey stick. Presumably, there were times when it didn’t. M&M just helpfully provided a graph that showed what it looked like the times that it did. And by gum, the times that it looked like a hockey stick, it looked like a hockey stick. Only smaller.

        To me it looks like the wording of the paper was crafted with an eye toward governmental testimony where a defense against perjury is a true statement. But what do I know?

        If we wanted to take M&M’s aggrieved tone and infer something, well, that’s not M&M’s fault. Aggrieved tone? they could ask. Well, we were just pointing out that sometimes Mann’s code produced a hockey stick shape with random data. Of course, there were times when it didn’t. We never said it did. And if the data had a hockey stick shape in it? Well, that’s beyond the scope of the paper.

        Yes, Judith, M&M’s paper is small potatoes.The whole cottage industry based upon a hunting of the snark would be, wouldn’t it? I was a chump to think otherwise.

        “It’s a Snark!” was the sound that first came to their ears,
        And seemed almost too good to be true.
        Then followed a torrent of laughter and cheers:
        Then the ominous words “It’s a Boo-“

      • You clearly haven’t read MM05 (GRL)

      • “The simulations nearly always yielded PC1s with a hockey stick shape, some of which bore a quite remarkable similarity to the actual MBH98 temperature reconstruction – as shown by the example in Figure 1.”

        I mis-remembered the text (“nearly always” instead of my memory’s “often”) but the substance is unchanged. “Nearly always” actually means “Not always”. Which means (necessarily) that some didn’t.

        The graph which displayed the “similarity” used a Y-axis 10 times smaller than Mann’s. As if the graph were a 1955 sci-fi movie gila monster.

        Here are the two graphs:

        http://deepclimate.files.wordpress.com/2010/10/wegman-fig-4-1.jpg

        For the snark was a boojum you see.

    • I am all in favor of sorting out the merits of the different arguments on both sides. lets lay it all out.

      • Dr Curry
        As a layman in climate science I’m intrigued to know how you propose to examine the merits of “both sides” while at the same time you (and the echo chamber here) fling words like “dishonest”, “pseudoscience” and “lazy” around.

        Call me naive, but I’d have thought the first prerequisite for any honest appraisal of the facts would be the absence of mud-slinging.

      • SteveC2: 1
        Judith: 0

      • Grow up.

      • OH SNAP. nice retort

      • Steve,
        What if Dr. Curry is right? What if you looked into the issue and learned that Jones, Mann and the rest had violated the standards of science, hid the fact papers had failed verification statistics, truncated data and the rest? What should Dr. Curry do then?

        Is it possible to examine both sides when one side is using tactics perfected in pseudoscience and not expose those tactics? Can one “lay it all out” and not discussed these violations of the standards of science?

      • Ron
        If Dr Curry is right, what need of “dishonesty”, “Pseudoscience” etc.?

        But let’s see what Dr Curry has to say…

      • Steve,
        Answer the question. Is it possible to look at both sides without commenting on these kinds of violations of scientific standards? She is not name-calling because she disagrees. There are important scientific standards that have been violated. If you have not looked into these issues yet, you should.

      • SteveC2,
        so was it OK for the RC gang to call nearly everyone in the world who disagrees with them ‘denialists’ or to seek to censor the skeptics work or to break FOIA to stonewall releasing data?
        You may be a layman, but you are certainly a partisan.

      • “so was it OK for the RC gang to call nearly everyone in the world who disagrees with them ‘denialists’ ”

        Yes, if they are ill-inofrmed and are denying the evidence presented.

      • ianash,
        Your view of what is ill-informed and denying of evidence is breath taking in its reactionary ignorance.
        Please do continue your self-immolation. But is it carbon neutral?

      • Lift hunter lift!
        You can do better than that. The hive mind needs you. Protect the Queen!

      • You’re arguing with a 4 y/o. But, it is indicative of mentality. You asked if it was ok to break laws…….he said yes. You asked about censorship and he responds by saying “if they are denying evidence presented.”…………newsflash! Censorship denies the presenting of evidence. Maybe English isn’t the first language of ianash.

      • Way to make stuff up suyts! Do you even understand the issue?

      • I made nothing up.
        Hunter: “..seek to censor the skeptics work or to break FOIA…”

        ianash: “Yes, if they are ill-inofrmed and are denying the evidence presented.”

      • “lets [sic] lay it all out”

        Yes, let’s.

        Judith Curry.

        You obviously disagree with the recontruction, or you would not have started this thread.

        Can you post data describing a trajectory that you believe represents the warming in the last one thousand years, as you accept it?

      • That would involve doing science. Unlikely at the best of times with this one.

      • If you disagree with string theory, do you have to come up with an alternative in order for your criticism to be taken seriously? You’re essentially putting forward the argument that in the absence of an alternative, an incorrect methodology is useful. This is clearly nonsense.

      • Argumentum ad ignorantium.

      • Which reconstruction do you support – and why?

      • Nobody can do what you ask because we only have empirical evidence for the last century and a half (which has its own problems). All else is hypothesis and conjecture. We will never have undeniable proof of what the planet was like past that point.

      • Steven Sullivan

        Here? You’re kidding , right?

        Be a scientist, Judy. Collect some data, find some collaborators with skills to aid you, and do an analysis. Or a meta-analysis of already-published work. Send it to a peer reviewed journal . ‘Sort it out’ in the literature, not on a *blog* teeming with ‘skeptical’ mad-as-hell howlers who seem even understand where to find the published claims they’re shaking their fists at. (It’s telling that the AR4 quotes that Grypo posted seem *new* to people here, well into this ‘discussion’. )

        Attention howlers: See, the dendro proxies *aren’t* the only proxys used in reconstructions. See, the AR4 *does* discuss the divergence problem. See, the dendro proxies *do* track temperatures for most of the period that we have very reliable temperature records, i.e., post 1880. See, the divergence problem concerns a *subset* of tree ring data since ~1960, *not* all of it. Even wikipedia (“Divergence problem”) could’ve helped you there: “Samples from southern forests do not exhibit this divergence, though this could be due to paucity of samples, and not all trees in the northern hemisphere do. Divergence is most common in the far northern hemisphere.”

        See, even howlers can go to the journals if they really want to (if one of the two links below doesn’t work you can likely get free online access at your local university library ).

        D’Arrigo, Rosanne; Wilson, Rob; Liepert, Beate; Cherubini, Paolo (2008). “On the ‘Divergence Problem’ in Northern Forests: A review of the tree-ring evidence and possible causes”. Global and Planetary Change (Elsevier) 60: 289–305.
        http://www.ldeo.columbia.edu/~liepert/pdf/DArrigo_etal.pdf.
        http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.167.728&rep=rep1&type=pdf

        (See, *14 papers between 1995-2006* about the divergence problem referenced in the paper’s introduction — that’s ‘hiding the decline?)

  25. Fantastic post Judith!

    It’s great to see Gavin engaging in an environment where he can’t hide behind moderation. I think he needs a little more practice at it though. Perhaps you could winkle him out of his shell a little further by offering a guest post, followed by a science/maths based Q and A, heavily moderated for relevance.

    Or perhaps you could ask a series of searching questions concerning the pal(eo) papers and their claims of “robustness”.

    ….now I must get back to work!!!!!!

    Boy I would love to see that

    • Steven Sullivan

      I doubt you even read RC. If you did you’d see RC moderators engage ‘skeptics’ time and time again in comments. Look up a recent exchanges with ‘TimTheToolMan’ re: Lindzen’s unsupported claims, for an example.
      http://www.realclimate.org/?comments_popup=5257

      RC mods’ patience with the willfully muleheaded is low, certainly (and that’s a not uncommon impatience among scientists I know). Once something’s been explained multiple different ways, and once they’ve been given the references to continue their own education, there’s not much point in continuing to engage someone who doesn’t want to understand.

      Their patience for spewers of oft-debunked zombie memes is zero, and I applaud them for that. Wish more blogs would show the same impatience (hint).

      • Steve,
        I think you need a reality check. Moderation at Real Climate is more like censorship. Anyone arguing points with them experiences it. Brain dead piling on by the RC disciples however is positively encouraged.

      • You know David, that’s very insightful -> I hadn’t thought of it that way. The Real Climate assertion that “we moderate away the repetitive arguments of people who just don’t want to learn” is in fact falsified when they *fail* to moderate warmist repetitive spam!

        I wonder if someone could do a study on that -> parrot the warmist line in a trollish way on RC, and see how many comments actually get moderated out :)

        My bet is that out of 100 trollish warmist comments, exactly zero will get moderated out. Any takers on more than zero? :)

  26. Judith,

    A few things that stand out to me and I would have highlighted:

    From the IPCC TAR:
    Mann wrote that “everyone in the room” agreed that the Briffa series was a “potential distraction/detraction from the reasonably consensus viewpoint we’d like to show”.

    and

    Briffa recognized there was “pressure to present a nice tidy story as regards ‘apparent unprecedented warming in a thousand years or more ’”, but expressed many caveats, in particular that the proxies were not responding the way that they were supposed to and that that the recent warmth was “probably matched” 1000 years ago.

    I don’t read honest science in those statements, they were creating a story for consumption, clear and simple. That is not science.

    • You should note that your quote isn’t “From the IPCC Tar”.

      It’s from Stephen McIntyre’s interpretation — “a story for consumption, clear and simple. That is not science.”

      Hope that helps.

  27. For me, the main problem with the “hide the decline” episode is not the issue itself, but rather what it represents, and the consequences of that. Let me explain:

    The “hide the decline” and “Mike’s Nature trick” is an issue that is perfectly easy to follow. All I have to do is read the detailed accounts and contexts, and give fair reading to multiple viewpoints, and then I can easily make up my own mind. It’s all there and plain to see. From having done this, I KNOW that it’s not merely “a neat way of solving a problem.” It is gob-smackingly obvious that issues of PR have triumphed over accuracy in this instance, as with many other instances here and there. My point is, I don’t need anyone to explain it to me. And if someone tries to tell me it’s merely some sort of unfortunate colloquialism, and doesn’t mean what I already know it means, then I know one of two things about that person: either a) they haven’t bothered to look at the details themselves, and so they can’t be trusted; or b) they have all the facts at hand and are lying about it, and so they can’t be trusted.

    Here’s the problem. The vast majority of science is built on trust. I’ve never actually measured the distance, say, from the Earth to the moon. I have to rely on the experts, and trust that they’ve done their job. Nearly everything I know – from news accounts in Tunisia to the atomic weight of hydrogen – represents something I don’t have either the ability, the time, or the inclination to investigate for myself. Even the peer-review system is built on trust. Reviewers generally give a careful reading and decide if the outcomes are novel, and the procedures sound, etc. But they also assume that the author is not being duplicitous – not fabricating results or deleting data or lying about methods. It all comes down to trust.

    And so the great tragedy of this corruption of climate science (in the original sense of the word “corruption”) is this: there are some things I cannot investigate for myself. There are some thing I don’t have the ability, or perhaps the time, to devote myself to, in order to fully understand exactly what was done and decide for myself what it means.

    Years ago it took me half a day of searching online to discover that the Vostok ice core has a resolution of something in the neighborhood of 900 years. This, still, is not easy data to find. Thanks to the William Connolleys of the world, even Wikipedia won’t give up this simple fact. Now I understand … such information “dilutes the message” and is a “potential distraction” from the clear, consensus view. But I finally figured it out. And I know – I don’t need someone to tell me – that 900-year smoothed data cannot and should not be sliced in with Mauna Loa yearly CO2 data. And yet it is, constantly, by people who should (or do) know better.

    What this leads to is this: I just can’t investigate every issue for myself. I read about other paleo proxies and alternative methods for measuring CO2 levels – such as this account – and I simply don’t have the ability or the tools to figure it out for myself. What would be nice is if I could just assume that it’s been given a fair reading, by people who know about this stuff. It would be nice if I could just read the next IPCC report and get an unbiased summary, in the context of all the other relevant science on this issue and others.

    But now I know I can’t get that. I know that climate science has been deeply corrupted by the politics of AGW, and even good scientists are sometimes afraid to challenge the orthodoxy. And so, for the stuff I can’t figure stuff out for myself, I’m just left to wonder how robust these results are, and how well investigated. Were CO2 levels really 350 ppm 12,000 years ago? Does CO2 persist in the atmosphere for hundreds of years, as with the current climatology meme; or were all the physicists, chemists, geologists, etc., right when they pegged it at 5-6 years?

    Now, unfortunately, it’s very hard to know. And I have to assume these non-conforming results have NOT been given a fair hearing, because the bums who are supposed to do so keep telling me “hide the decline” wasn’t a big deal.

    Right. I may be dumb, as they say, but I’m not stupid.

    • Ted – You’re clearly neither dumb nor stupid, but you are vulnerable to confusing the level of blogosphere attention to inappropriate behavior with the actual degree to which it reduces the reliability of climate science conclusions. In a polarized debate atmosphere, perspective is hard to achieve even for brilliant practitioners in a different discipline.

      I’ve commented above on my perception that climate science in general performs admirably, and despite lapses that warrant correction, deserves as much trust as other fields that have also contributed important scientific advances – one needs to balance the positive against the negative, because no form of human endeavor is free of negatives.

      Finally, apropos of atmospheres, you should feel free to ignore the article by Segelstad on the lifetime of excess atmospheric CO2; the article totally misunderstands how that is evaluated and mistakes the turnover time of CO2 molecules with the decay time of a concentration excess – the latter is characterized by multiple decay constants rather than a single half-life, and these vary from decades for a fraction of CO2 to hundreds of thousands of years for another significant fraction.

      • Fred, thank you for the nice comment. I’m afraid I don’t share your assessment that climate science in general performs admirably. My view has certainly been informed by information in the blogosphere, but it is by no means dependent on it. Mainly, it comes from repeatedly – repeatedly – diving deeper into an issue to get the real facts, and finding that the science doesn’t actually support the conclusions.

        The popular press is the most egregious, of course, but the scientists themselves quite often fall into hyperbole or confirmation bias. I’ve looked up references and have found that they are mis-characterized. I’ve read research papers and found them to be weak or poorly designed, and wondered how they could ever have been published. (Here is <a href="http://climateaudit.org/2010/11/06/phil-jones-and-the-china-network-part-3/#comment-245106"one example, on the UHI effect – an old, poorly done paper that is still cited by the IPCC.) And I’ve come across so many examples of double standards, ad hominem attacks, and groupthink by climate scientists that its a wonder there’s any room for dissent at all.

        Unlike the more, hmm, vocal skeptics, I don’t view all this as some grand conspiracy. The AGW proponents truly believe that the most important issues in climate science are thoroughly settled, and that the consequences are dire … and that’s where they are the most dangerous, when it comes to the scientific process. Gavin, or Michael Mann, or Phil Jones – heck, even “death train” Hansen – believe themselves to be right. So much so, that any skeptical argument is seen first as a PR issue, rather than an honest attempt to get the science right. The knee-jerk reaction seems to be: any skeptical paper or blog post is badly done, or meant to confuse the issues, or funded by Big Oil, or is otherwise useless.

        Thankfully, we had Climategate, which prompted many true scientists – our gracious host among them – to take a second, more careful look. So I am hopeful that the science will get better, and the true scientists will more often point out when the emperor has no clothes.

      • Judy – apologies for the mistyped link above. -t

      • Fred, as you said, “one needs to balance the positive against the negative, because no form of human endeavour is free of negatives”. Based on that, I choose to call all the published papers, & the opinions of “The Team” who control climate science, as the negatives in the endeavour of climate science. Of course, you will not agree, but an impartial observer would say that Gavin Schmidt has shown by his above comments that he is aggressively defensive of a fellow” Team” member in the face of a very reasonable argument that he is defending the indefensible.

      • Fred “climate science in general performs admirably”

        I’m interested in how you arrive at this assessment. Can you, for instance, name any solid, empirically confirmed discoveries achieved by climate “science” in the last, say, twenty years?

      • Fred, with respect, climate science performs as admirably as political science. Both rely heavily on statistical analysis and confidence intervals. Within both realms modeling is used to make best-effort representations of reality. While both have methods to explain the reality of the past, both are less successful at predicting a future reality. I am quite willing to accept the predictive uncertainty of future reality within the context of these sciences. In both fields practitioners are working on complex systems.

        Where climate science has run into peril is its hijacking by the scientists who cross the line into advocacy and rhetoric. At this point seeking the truth is overtaken by persuasion. Plato pointed out in the Gorgias that rhetoric and persuasion is not a way of seeking the truth.

        I am not a political scientist – I am an engineer who happens to have political science and philosophy of science as a hobby. I started following AGW before Climategate, but when the Climategate emails were published I became outraged at the corruption of the scientific enterprise by scientists who crossed the line into advocacy and rhetoric. There may be only a few bad apples in the barrel but these are the bad apples that informed the alarmist rhetoric flowing from the IPCC reports that governments relied upon to make policy decisions with billions of dollars of public funds.

        For me this “hide the decline” incident put doubt into my mind about the integrity of climate science. It brings to mind the cold fusion claim that broke while I was an undergrad student. Physicists around the world tried to replicate the experiment but couldn’t and excitement turned to disappointment. The hypothesis of low temperature fusion was resoundingly falsified but its failure did not affect the integrity of the scientific enterprise in physics.

        In the long wake of the Climategate emails my doubts about the integrity of climate science still linger. Its credibility now rests upon a choice. When its practitioners inevitably admit that there is corruption, will they embrace the words of Louis Brandeis: “Sunlight is said to be the best of disinfectants” (no pun intended)?

    • Great post Ted.

      I agree that trust is the central issue here.

      Had “the trick” been an honest mistake, or something that happened in the stress of the final hours of preparing the report, that would have been forgivable, if it was admitted as being a mistake and publicly corrected.

      That way we could have hope of things being done better in the future. Trust would be rebuilt to some extent.

      But as long as mistakes are not admitted but staunchly and aggressively defended, there is no hope. It is proof of a continuous intention to deceive, casting doubt on anything else that might come out of the IPCC and associated partners.

      A sorry state.

      • Trust only comes into it in the public arena and only then for making decisions. If no action is to be taken, it’s irrelevant how good or bad the work is – it’ll all get worked out internally eventually. When I make an important decision, trust doesn’t come into play much. I either have some kind of validation of the information I’m using, or I don’t. I understand the implied risks of using unvalidated information can be rather large.

      • I basically agree, but a point that is often missed in discussion of this issue is that the problem is not decline.

        The problem is hide. There is nothing imaginable that is more contrary to scientific tradition and method than that.

      • Steven Sullivan

        Nonsense. Complex data and models are simplified all the time for pedagogical purposes, e.g., textbooks. Exceptions to general rules are omitted or alluded to in passing. Science is OK with that as long as the complexity is actually represented in detail in the scientific literature…which in the case of the divergence problem, it certainly is.

      • The “divergence problem” is not a problem; for the conclusions which Mannean dendroclimatology tries to draw, it is a catastrophe, showing that the underlying assumptions are untenable.

        As to “represented in detail”, this might have some validity if the point were unambiguously emphasized in such “authoritative sources” as AR4 and specifically underlined in the Summary for Policymakers, which is all that our idiot politicians and journalists ever read (if they ever get beyond the press release). But of course it was not; to the contrary, the “divergence” was buried as carefully as a diseased corpse in the verbose, opaque prose of the “scientific” sections.

  28. There is another aspect to the Hide the Decline, and that is the use of end-point padding to create the smooth graphs so loved by the dendros. To present a nice message, annual data won’t do because it is too noisy. So some sort of smooth/filtering is done, like a 30 or 50 year centered gaussian or other filter. This is fine (more or less) until you reach the end of the data and then your smoothed curve might have to stop in 1980 and won’t leap into the sky. McIntyre found (and others) that Mann etc used various types of reflections and padding that would continue and amplify an upward trend right up to 1998 or 2000. But when temps stopped rising after 1998, this type of filter misbehaves and they conveniently changed the type of padding used in the GISS smoothed graphs and others (and IPCC). This type of end padding is unjustified and exaggerates warming trend certainty in the most recent years.
    Another reason all this is important is that paleoreconstructions have been used to test climate models, including the original Mann recon that is so flat.
    Finally, a multivariate test of the primary recons in IPCC 2007 showed that they do not agree with one another in terms of patterns of fluctuation at any time scale as a group, but only in pairs and 3s (at home now so no reference) and then not with any impressive level of agreement. This suggests that they are NOT capturing multidecadal to centennial patterns well and are not giving a basis for making statements about the world, either due to including bad proxies, funky math, untested assumptions, or other.

    • Craig,

      I totally agree with how they handle the endpoints as mathematically corrupt. This is an important point that is difficult to explain easily, and falls on deaf ears.

      If you have a whole bunch of very noisy data and you heavily average it, it will flatten it. But if you leave just the very last part of it un-averaged, of course it is going to look like the end of the graph is all of a sudden changing wildly. Hello HS (up or down).

    • Phil. Felton

      Yes Craig, you had the same problem with your paper and desperately weaseled around to try to connect the end of your smoothed data (1935) with the present! Even going so far as to verbally ‘splice’ the instrument record onto the end of the proxy record.

  29. “Can anyone defend “hide the decline”? I would much prefer to be wrong in my interpretation, but I fear that I am not.”

    Judith, I agree with Bob, above, with regard to the precise thing that you want to be wrong about. As far as I can tell, you’re desiring that your eyes deceive you. They do not. The decline was hidden. You are right that it should not have been hidden. Hiding the decline will always be, as it always was, a dishonest act of misdirection in the reporting of scientific evidence.

    I see Gavin is very much away on a blustery tangent, not in any way addressing the crux of the issue – the actual practice of splicing disparate series to create an illusion of tree-ring proxy veracity in the paleo record. This act is an affront to the ethos of dispassionate scientific endeavour.

  30. Gavin,

    If you attempted posts of such content at RC they would never be posted.

    Chew on that for awhile.

  31. In his original ClimateAudit post “IPCC and the trick” on “hide the decline, Steve McIntyre made the following accusation.

    “After the Arusha meeting, Briffa hurriedly re-did his chronology and the new version was delivered to Mann on Oct 5, 1999 – it was this version that had the big decline. In the First Order Draft of Oct 27, 1999, IPCC author Mann deleted the post-1960 portion of the Briffa reconstruction plus other things that I don’t yet quite understand.

    The particular accusation against Mann is unequivocally false. It never happened. The version that was delivered on Oct 5 was not used in the First Order Draft, which in fact used an earlier “low frequency” version of Briffa (similar to the Briffa and Osborn in Science 1999). At Mann’s later request, Tim Osborn resent the newer data set in time for the Second Order Draft, where it first appeared. But that version of the data set only went up to 1960. So once again nothing was deleted by the IPCC.

    See:
    http://deepclimate.org/2010/05/14/how-to-be-a-climate-science-auditor-part-2-the-forgotten-climategate-emails/

    Also, I demonstrated that the particular splicing of Briffa with instrumental data claimed by McIntyre was highly unlikely. And, in general, padding with the average of final values vs instrumental values would have made very little difference to Briffa’s series in any case. And the Jones series was clearly not padded with instrumental values.

    See:
    http://deepclimate.org/2010/06/29/revisiting-tar-figure-2-21-part-1-another-false-claim-from-steve-mcintyre/

    • So does this mean the graphs in the TAR and AR4 and the WMO Report aren’t misleading? What a relief.

      • Judith, at the end of your blog post you issued the following challenge: “If there is a problem, lets get to the bottom of it and fix it. ” I, and apparently DeepClimate, thought by this that you cared not just about whether they were misleading but how they came to be misleading. Otherwise, how do you intend to fix or prevent whatever errors were made?

      • You are falling for the ruse – it’s about stirring up the locals, not really debating the issues.

      • While I might not agree with Gavin on much I note that at least he has the courage to put his real name on his posts and let the comments fall from there. You on the other hand hide behind anonymity and make not only rude but vile statements. I am not a scientist and therefore I follow the tone people take. You strike me as someone who would have a hard time maintaining a middle school social life chasing every one who might disagree with you but still like you off because they disagree with you. It is this tone that has convinced me that the members of “the team” are hiding something. They remind me of my teenagers when caught hiding something from me. Lots of arm-waving and denials but the more shrill the denials the more certain I am that I am on the right track, and you and others like you are getting extremely shrill.

      • At least there is an admission of errors.

      • Steve McIntyre

        Judy,
        Clarke states that it is not presently established whether Mann or Briffa deleted the post-1960 data in the spaghetti graph (Fig 2.25) in the IPCC First Order Draft (dated Oct 27, 1999). Clarke observes that it might have been Briffa, rather than Mann, who physically deleted the post-1960 data in that graphic.

        The assignment of responsibility as between Mann and Briffa, while perhaps important to the institutions involved, is surely irrelevant to the practice of hide-the-decline itself. Regardless of which of them physically deleted the data, it doesn’t justify the practice. In any event, the evidence seems clear that, regardless of which of Mann or Briffa physically deleted the post-1960 data, the other party endorsed the practice and thus responsibility is joint and several.

        I also note that Dave Clarke aka Deepclimate discussed my December 2009 post (written in the immediate wake of Climategate) rather than the later and more detailed exposition in May 2010 to which you linked. My December post attracted comments that clarified the chronology in my initial exposition – something that I noted in an update to that post. For example, Clarke observes that Briffa participated in a hide-the-decline incident prior to October 1999 (the deletion of post-1960 data in Osborn and Briffa (Science May 1999). Quite so. I reported this in the May 2010 article that you linked to.

      • In any event, the evidence seems clear that … the other party endorsed the practice and thus responsibility is joint and several.

        And isn’t that the case, in a deeper sense, with the great lengths the whole Team went to refuse to face the fact that Hide the Decline was rotten science.

    • Sorry Deep, but the fact that the post-1960 data were deleted before being sent to Mann does not make it ok, and the splicing in of instrumental data has been clearly shown by a data audit, which I followed in detail.

      • The WMO graphic was one graph in a summary report that contains no footnotes or reference page. It is clearly intended for a general audience and as such, a certain degree of detail is lost, as it always is in this kind of document. Take this publication of the International Astronomical Union – it is similar in purpose — a summary of the work of the IAU for the year. No footnotes, not references. Just summary of the work and intended for a more general audience.

        The WMO graphic could have been better labelled, as the inquiry into the CRU found, but it was one graphic in a public summary report that is over a decade old.

        That this is still being trotted out by contrarians and put on display still suggests to me that it is done for political rather than scientific interest.

      • The decline was hidden for political reasons, by those on political paychecks. For shwonk to accuse those who point this out of being political, is disingenuous.

      • punksta, please provide proof that there was political motivation and political paycheques.

        That the whole “hide the decline” meme / chum is now being promoted for political gain is not in question.

      • It is very difficult to proove such things, even if seems an obvious reason why the graph has been presented in this deceptive way.

        Because the omission of the decline is deceptive: it hide a crucial parameter that allows the general audience to forge a personal opinion about the validity of tree ring as proxy thermometer.

        Without the decline, as a non-specialist, I had no particular reason to doubt the usefulness of the proxy, it makes sense that the growth of trees is influenced by temperature, even if as a gardener, I also have strong suspicion it is not the only parameter so I expect quite large error bars

        With the decline, as a non-specialist, I conclude that the curve is meaningless and that tree rings are not usefull as proxy thermometers. To convince me otherwise, you will have to expose much more than this curve, which is not possible in a summary.

        Any book on data presentation….well, common sense too, tells u that the fact that hiding available info to add perceived robustness to a interpretation is dishonest, especially in a summary where there is no place to present the raw data and discussions…

      • With the decline, as a non-specialist, I conclude that the curve is meaningless and that tree rings are not usefull as proxy thermometers.

        If the specialists disagree on the implications of the DP for the meaningfulness of the curve and for tree rings as a useful proxy shouldn’t I, as a non-specialist, be even more circumspect?

      • The detailed discussion I have read from specialists mouth on the DP cast doubts on the validity of tree rings as a useful proxy. Some of them say that although the DP is unexplained, they have reason to believe tree rings can be used before industrial period. Other says that they do not have those reason.
        So you are right, specialist do not agree to unconditionally rules out tree ring as T proxies.

        But I am also right: specialists agree that DP CAST DOUBTS on treemometers accuracy (those 2 propositions are not mutually exclusive, I hope you can see it). They better do, else I would have serious doubts about the logical capabilities of the specialists who don’t.

        As DP cast doubt on the accuracy of the reconstruction, it is dishonest to remove it from a curve, especially from a summary where it is the only information available to the casual reader.

        I try hard to be openminded on this (not easy, as a skeptic I come with my bagage, as you come with yours as a warmist), but really, I can turn it on any angle you wish, I can not see how removing the DP can be defended as the correct way to expose the data as objectively as possible. It can be defended as the most effective way to expose an evidence of AGW, but this is not the same thing. Far from it, and if you do not see the difference there is no hope for you to do Science (as in advancing human knowledge), only scientific advocacy (as in defending a theory with technical-like arguments)

    • AH its dave clarke.

      DC. nice

    • funny how DC considers McIntyre so important, a discussion about hiding declines becomes an analysis of what if anything McI has ever been wrong about (and am not saying he has)

      can’t help wondering if in the world of DC poor Mann and Briffa and Schmidt are but tools of evil climateauditers remotely controlling them sometimes even back in time

  32. I admit that I am not an expert, but from what I have read of the literature, it seems to me that the divergence problem, far from suggesting that scientists should drop all the tree ring data, or that it undermined the reliability of the tree ring data, instead provides a new avenue for study and understanding both of trees and their response to environmental stimuli but also the consequences for the ability of northern forests to act as carbon sinks.

    As I understand the literature, not all trees show divergence and not all trees that show divergence do it to the same degree. The fact that trees, even divergent ones seem to follow the instrumental record well prior to the 1960s suggests that there is something specific to the post-1960 era that is responsible for the divergence problem. Some possible sources examined by D’Arrigo et. al. include drought stress due to warming, global dimming due to aerosols, ozone depletion, pest infestation – all of which suggest anthropogenic and related influences. The fact that trees track the instrumental record well until the post-60s suggest that they can be useful prior to these anthropogenic influences.

    Of course, as Feynman said, “Scientific knowledge is a body of statements of varying degrees of certainty — some most unsure, some nearly sure, none absolutely certain.” I take the divergence issue as part of the unsure body of statements that make up scientific knowledge. Doesn’t mean scientists have to throw out tree rings. I would think that the divergence problem makes the issue even more interesting from a scientific point of view and if this whole matter hadn’t been so politicized, it would be one of those areas of research that would yield up much important knowledge about climate and dendroclimatology.

    • “As I understand the literature, not all trees show divergence and not all trees that show divergence do it to the same degree. The fact that trees, even divergent ones seem to follow the instrumental record well prior to the 1960s suggests that there is something specific to the post-1960 era that is responsible for the divergence problem”

      – well, my understanding is that there is another entire subset of tress that don’t show any correlation with temps in the calibration periods. So, we have some that correlate during a specified period, some that don’t, and then some that do correlate in the calibration period but then ‘diverge’ (by differing degrees) later on. This only screams out to me to be a HUGE opportunity for spurious correlation. This stuff is just very unintuitive to me. I must be missing something as to why some insist on putting so much weight into the dendro-paleo studies.

      • Amazing. So, contriving a valid set of tree proxies is a tough thing to do?

        Knock me down with a feather.

        I know some people who can just squint at a stand and tell.

    • “The fact that trees track the instrumental record well until the post-60s suggest that they can be useful prior to these anthropogenic influences. ”

      But ok, so for 100 years it tracks well, and for 50 it doesn’t. Did it track well 300 years ago? 500? 1000? 5000? Since there’s no instrumental data at those points, it’s impossible to say. You’re stipulating that the last 50 years are an abberation that can be discarded, but that’s not proven in any way. What the discrepancy shows us is that the tree rings don’t track temperature alone (or even, at all?). What DOES it track? Impossible to say at this time… but claiming that it’s temperature requires a leap of faith that all past extrapolations of tree ring temperature follow the same trends as the “good” tree rings. We don’t know that, and science shouldn’t be about faith.

      • I suppose it depends on why it doesn’t track well in those 50 years.

        From what I understand, there is a physical basis for tree ring growth to track temperature and other climate variables. It’s not faith.

        Again, just because we don’t know everything doesn’t mean we know nothing.

        And I try not to mistake my own ignorance for that of scientists. Just because I personally don’t understand something doesn’t mean the scientists who study the field are equally ignorant…

      • Shewonk- you said, “The fact that trees, even divergent ones seem to follow the instrumental record well prior to the 1960s suggests that there is something specific to the post-1960 era that is responsible for the divergence problem.”

        Part of the problem is, the calibration period for these studies is from 1881 – 1960. That leaves very little temperature data to perform validation on, particularly if the post-1960 data is excluded. So, I think it “follows the instrumental record well” simply because it was largely calibrated against the instrumental record.

      • ‘So, I think it “follows the instrumental record well” simply because it was largely calibrated against the instrumental record.’

        You know. I bet there might be some scientific literature on this very problem.

      • The main problem is that tree rings don’t respond to temperature in a linear way. The real response is an upside down U-curve with a temperature optimum (all other items like precipitation being equal). Part of the divergence problem may be that some species are over their optimum temperature. But there is no way to tell us which species has had a divergence in the far past, if the real temperature was higher than today (which is the case in the bristlecone area of the SW USA), even if these have no divergence problem today.

      • I did not know that- though in hindsight it seems obvious.

        Dumb question, has anyone.. erm… calibrated the tree response? I.e. has anyone defined the U-curve for the individual species?

      • Yes, see my post below

      • Excellent- thanks.

      • Craig i can only seem to get the abstract- am i being dense?

      • Labmunky

        Tree growth and plant growth are somewhat complex. They respond to temperature, total daily sunlight, moisture content of soil, etc. In the case of sunlight much of the spectrum is irrelevant – typically there are two bands in the visible spectrum which drive development. The details are all species dependent.

      • Yes i’m aware of this- it was kind of a rhetorical question.

      • “I suppose it depends on why it doesn’t track well in those 50 years.

        From what I understand, there is a physical basis for tree ring growth to track temperature and other climate variables. It’s not faith. ”

        You understand that because it’s what they want you to understand, but it isn’t known with any degree of certainty (if it was, they could tell you WHY the divergence.). You’re accep[ting their word for it that the tree rings are an excellent proxy for temperature, with limited information. That’s faith. With limited calibration, they can be an indicater at best, not a proxy for temperature because they don’t know all of the factors that will influence growth, clling into question the reasons for behavior in the past. Science doesn’t allow you to wave your hand and make data magically dissappear. You need facts to discount the 1960 decline… so far, they dont exist.You’ve speculated on reasons, but speculation isn’t a fact either (despite what Climate Science says.)

        “And I try not to mistake my own ignorance for that of scientists. Just because I personally don’t understand something doesn’t mean the scientists who study the field are equally ignorant…”

        Here we have the classic appeal to authority… “surely they must know if they make these statements!” Or they are being disengenuous and not giving the public and policymakers all of the facts and highlight problems with their current understanding since that would tend to undermine their bully pulpit.

      • Here we have the classic appeal to authority… “surely they must know if they make these statements!”

        Which authority is a layperson to appeal to — the majority of scientists or the few dissenters? I only know that as a layperson who doesn’t have the scientific background to judge the value of any given paper or discipline in science, I am better served, in the long run, to stick with the consensus view.

        I suspect that many laypersons use their political compass to arbitrate scientific debates, as in “which side doesn’t threaten my cherished political values?”

      • So you just suspend any rational judgment in the face of lots of people who assert themselves to be right? No thought of tryng to make your own assessment?

        You must be an ad mans dream consumer. A blank canvas on which they can write their message. And an even better target for con artists.

      • Some people are capable of making a rationale assessment of their own strengths and capabilities and conclude that others know better.

      • ‘Trust me, I’m a climate scientist’??

        Works for some, I guess.

        But it reminds me of the three great lies of humanity:

        1. The cheque’s in the post.
        2. Honest I’ll still love you in the morning.
        3. I’m from Head Office I’m here to help you.

        Maybe there’s a fourth around here somewhere……

        1

      • 4. My judgement of my own capacity is always accurate and never inflated by ego or ignorance.

      • I’m glad that you are so self-aware. But somewhere the humour is missing in that remark.

      • You meant ‘irony’ perhaps?

      • Yes Lat there is a fourth and a fifth, both from the gentler sex and posting either would probably get me banned.
        Suffice to say, getting banned would be hard to swallow.

      • I’d love to do a PhD in dendrochronology / climatology but alas, I have to feed my family and don’t have the years of time to spend. But I still have to decide who to support when it comes to electing politicians. I have to decide which one is likely to listen to science and do the right thing when it comes to policy. My dilemma is that I don’t have the expertise and I know it to judge the value of the work of Briffa and Esper and D’Arrigo and other scientists.

        That’s the crazy thing about this modern society with its specialization and division of expertise. Some of us just know more about things than others due to the 10 – 12 years of post-secondary education and years of research cred it takes to become a peer in a given science field.

        I recognize that I don’t have the capacity to make a valid analysis of the years of literature and theory and so I trust the consensus of the practicing scientists in the field based on their assessment of the peer reviewed literature. To do otherwise when you are a layperson and have no expertise is dangerous.

      • For what it is worth here is an idea: Consider which group is using ad hom attacks, appeals to authority, and other logical fallacies very frequently. History, and personal experience, tells me this is the group least worthy of trust.

      • Which authority is a layperson to appeal to — the majority of scientists or the few dissenters? I only know that as a layperson who doesn’t have the scientific background to judge the value of any given paper or discipline in science, I am better served, in the long run, to stick with the consensus view.

        I think this is a fair question and approach, shewonk, in the normal case. But the claim made by Professor Muller in the video Professor Curry links to is that hiding the decline is the very antithesis of normal science. I think his argument in the few minutes on this should convince anyone, even someone without any science background.

        But happily there’s no need to rely only on the video. Andrew Montford’s book The Hockey Stick Illusion lays out the detail in a way that many non-scientists have found very helpful. Even Judith admitted it helped her to see the wood for the trees in a sometimes confusing welter of competing blog posts.

        To read this book with an open mind and form one’s own view doesn’t go against using your heuristic in other areas. We all have to take some things on authority. But the possible corruption of climate science seems to me to be too important not to dig down just a little.

      • I suspect that many laypersons use their political compass to arbitrate scientific debates, as in “which side doesn’t threaten my cherished political values?”

        errr no, most sceptics have a pretty good inbuilt bull$hit detector.
        Unfortunately, the gullible lemming types don’t, so they have to defer to appeals to authority. Naturally enough, being gullible and a follower (lemming like) the authority they choose is the consensus one. (Safety in numbers for the unconfident if you prefer.)

      • Appeals to authority make sense if the authority is in possession of expert knowledge in a subject area and that subject area is the matter under consideration. Appeals to authority are fallacious when one claims that the person in authority can’t be wrong. I am not claiming that the scientific experts can’t be wrong, but that a layperson is better served to trust the consensus of climate scientists who publish in the peer reviewed literature over non-scientists who publish their non-peer reviewed musings on blogs.

        I don’t try to judge the scientific evidence because I don’t have the expertise, but I am just as good as the next person on judging if people are acting based on the desire to have reality conform to their political values. In fact, maybe more than most as that was at least part of my own area of study.

      • [Ipcc-style Climate Science has no “authority”.]

        shewonk, examples: in the realm of real science, peer review by a few has never been warranted to produce the “given truth”, and “hiding the science” in general has always meant that whomever is doing it is not practicing real science.

        In other words, the most basic problem with the science you are accepting as authoritative is that ipcc Climate Science is not real, scientific method and principle, science. One simple example of this fact is that the Climate Scientists in question have mislead anyone susceptible, as to the use and meaning of peer review in real science. That is, contrary to the behavior of certain Climate Scientists and what they often seem to be saying, peer review at a journal by a few selected peers has never been warranted to imply that the study then published is the “given truth” or anything even close to it – until the advent of “Climate Science”!

        At this point and even if you disagree, do you at least see why I’m arguing that CO2 = CAGW Climate Science has operated according to an unscientific definition of “peer review” and has, therefore, conveyed the wrong idea of what real science is to anyone who, especially through no fault of their own, is ignorant of what real science does?

        Because this anti-scientific concept of peer-review is also conjoined very closely with another way in which ipcc Climate Science behaves unscientifically, namely, that certain ipcc Climate Scientists – such as Jones, Briffa, and Mann early on – and Journals such as “Science” and “Nature”, contrary to their own stated conditions for publication, have failed to make available the “materials and methods” of certain critical studies, which are their “science”; so that their science can be reviewed after publication essentially by ‘everyone and their mother’, at least where the stakes are this high.

        In other words, real science necessarily includes the scepticism made possible by transparency of “materials and methods” as a component of the processing and confirmation of any alleged science.. Real scientists welcome the scepticism because they want their ideas to be able to stand up against all comers. Climate Science instead wants to thwart FOIA requests, made necessary themselves only because the Climate Science in question has not involved transparancy of its “materials and methods” to begin with.

        In fact, by not operating transparently and thus “hiding the science”, Climate Science itself has even managed to help prove again why transparency of “materials and methods” is essential to the practice of real science; that is, given what has been revealed subsequent to the time when this information – in the case of some critical Climate Science – was finally obtained by people outside of the closed circle of the essentially self-annointed Climate Science peers.

        There are many other ways in which ipcc-style Climate Science proves it is simply not doing real, scientific method and principle, science. Therefore, within the realm of real science, ipcc-style Climate Science has no “authority”.

      • Appealing to authority = suspension of critical thinking. If we’re going to stick to the science in the Popperian tradition then there is no authority to appeal to other than the truth which might be inferred through the say-so of a billion scientists but takes only one to conclusively falsify. But if we’re in the arena of politics and rhetoric, appealing to authority is a tried and true trick that is fair game.

      • Which authority is a layperson to appeal to — the majority of scientists or the few dissenters?

        Laah-daah-da-da-consensus-da-daa-da-daaa-da-daa.

        My favorite version of the Sleeping Beauty Waltz. Nice rendition, but derivative in interpretation.

      • I only know that as a layperson who doesn’t have the scientific background to judge the value of any given paper or discipline in science, I am better served, in the long run, to stick with the consensus view.
        You ‘know’ your appeal to authority/consensus is what you need?
        Even though this consensus is all funded from a common source, that has huge vested interest in the conclusions?
        And where the leading lights of this consensus have been caught trying to cook the books? And flatly refuse to change their ways or even apologise?

      • More unsubstantiated claims, Punk. Please provide some evidence.

    • My first thoughts were the tracking of the start of the use of Agent Orange, and the distribution of the diverging trees relative to the areas of initial testing and then heavy use. I would like to look at the persistence times and locations of airborne residuals relative to the sample trees in the study, if the data is still not being suppressed.

  33. Judith, I honestly thought I had something to say…
    …Until Ted Carmichael said it all, and better

    It is nice to see that Gavin thinks it’s only a difference of opinion on how a graph should be displayed.

    Sorta like getting your horoscope done, isn’t it Gavin………….

  34. The justification for hiding the decline was that somehow there was something different about that data in that time period that made it “bad” data, and so could be dropped. But nothing was ever shown to be the cause, and one can’t simply get rid of data you don’t like without a verified reason. And people can see this clearly.
    There is another trick, when dropping the Briffa post-1960 data, they had to renormalize it, and picked a base period different from the others and one that was much too convenient to make it line up with the others better. IIRC.

  35. I have done a detailed analysis of the divergence problem
    Loehle, Craig. 2009. A mathematical analysis of the divergence problem in dendroclimatology. Climatic Change 94(3-4): 233-245.
    available here:
    http://www.ncasi.org//Publications/Detail.aspx?id=3273
    One of the consequences of divergence is that past periods warmer than the calibration period can not be reliably estimated–they are suppressed. The the MWP will be underestimated. A second problem is that past responses of trees will be influenced by things like local forest conditions and precip, about which we have not data. This makes them unreliable.

    • Is that a peer reviewed journal? If not, why not?

      If the divergence is due to anthropogenic influences such as ozone depletion, or aerosols, and there was no similar era of such influences, I would think that you cant really make that assumption.

      You speak as though our knowledge of the “MWP” is certain enough to know if it would be underestimated. From what I have read, the MWP is thought to be a regional or hemispheric phenomenon.

      Just because we don’t know everything doesn’t mean we know nothing. To suggest otherwise is to be rather unscientific. We know something and we need to know more.

      • “Climatic change” is a first-line peer-review journal. If there is something special about after 1960, why do only some groups of trees show a decline? How do we know which ones will do so –we don’t. I demonstrated that mathematically when you use the methods of dendo reconstruction you will underestimate past warmth–try reading my paper before accusing me of things.

      • My apologies – I was unaware that you had published another paper. I was thinking of the two in E&E. Congratulations.

        How do we know which ones will do so? We don’t — but that doesn’t mean we just give up. It seems to suggest that we need to do more research so that we can know.

        At any rate, as I said, in less politicized circumstances, the DP would signal a fruitful line of research and might provide important knowledge relevant to both dendro and climate science. Instead it seems to have become a means of skeptics to suggest that we have to throw out dendro. I don’t think that’s valid. Can it be improved? Sure. Most science can.

        I went back and examined the original WMO graphic and related text. Could it have been better handled? Sure. Does it matter in the long run? No. IMO it’s a manufactured controversy conjured up for political hay-making.

      • Shewonk

        NCASI Members:

        “Any U.S. company that manufactures pulp, paper, or solid wood products is eligible to apply for membership in NCASI, as are companies that own or manage industrial timberlands. Currently, NCASI’s U.S. Membership numbers approximately 75 companies, which represent more than 90% of the paper and paperboard produced, nearly 70% of the wood panels produced, and more than half of industrial timberland acreage in the U.S.”

        Independent…like a train is free to travel wherever it wants…on the tarck laid down…

      • No one tells me what to publish or reviews my work. Google scholar me.

      • Umm, let’s see if I understand… Corporations that grow trees to make paper are Evil and Greedy, while Corporations that grow trees to feed utterly useless “biomass” plants for the sake of government subsidies are Wise and Helping To Save The Planet.

        I may be able to understand this eventually…

      • I agree the divergence is a distraction and it doesnt matter.

        So, for AR4 chapter 6. We should probably agree that Briffa should have shown the divergence that doesnt matter rather than hiding a divergence that doesnt matter.

        Ar4 has an errata. You’ll support putting the right graphic in that
        right? it doesnt matter so why fight it?

      • I’ll leave it up to the scientists to determine what constitutes and error or a difference in opinion over methods and the way to display data and evidence.

        What is interesting is to what use skeptics and contrarians put “errors”. Look at the “gates” that erupted when they found a few in AR4 – used them to squeeze out and amplify every ounce of doubt and smear as much as they could. Not in the interest of “sound science” as some proclaim but for political haymaking.

        As far as I understand, none of the “errors” — real or manufactured — found in the AR4 undermine radiative physics or the GHE or reduce the warming shown in the instrumental record.

      • As far as I understand, none of the “errors” — real or manufactured — found in the AR4 undermine radiative physics or the GHE or reduce the warming shown in the instrumental record.

        And who is claiming that they do? The issue is not the validity of the basic physics, but of the analyses being made and the credibility of those making them.

      • Steven Sullivan

        Yeah, their credibility is just *shattered* by a handful of ‘errors’ — all debatable either as actual errors, or as evidence of malfeasance — gleaned from a multi-authored document running to thousands of pages.

      • Making a mistake doesn’t undermine your credibility, defending it to the death does (“Voodoo Science”, anyone?). Is it a mistake to present “a nice tidy story as regards ‘apparent unprecedented warming in a thousand years or more'”?

      • Shewonk:

        “Just because we don’t know everything doesn’t mean we know nothing. To suggest otherwise is to be rather unscientific.”

        I agree with you but the point you are raising here is surely how to deal with the expression of uncertainty, especially with paleo reconstructions.

        This is why the ‘shaft’ of the hockey stick is so important. There is plenty of statistical evidence to suggest that the uncertainties in MBH98 – and all subsequent paleo reconstructions of the MWP – are so large as to make them little better than background noise.

        This really, really matters when the hockey stick graph has been used as the basis for so much government policy over the last several years.

        That we need to know more is beyond question – that we know enough already to confidently take action is far less certain.

      • This really, really matters when the hockey stick graph has been used as the basis for so much government policy over the last several years.

        What government policy in particular? Can you reference some that have specifically referred to the hockey stick or WMO graphic as supporting evidence?

        I don’t work in the climate policy field but it seems to me that whatever climate policy exists, it isn’t likely based on either the hockey stick or WMO graphic. When science is used to inform policy, it is usually the preponderance of evidence that is convincing rather than a single work. The basic physics, calculations of climate sensitivity and potential impacts are probably what would be influential in the determination of policy. But I would defer to an actual climate policy analyst.

      • The Labor government here in Australia most definitely used the hockey stick as the cornerstone of their argument that “the science is in” and that we must do all sorts of things to combat climate change.

        I’m trying to locate the actual document(s) which featured it. The website appears to have been taken down since the election last year.

      • ThinkingScientist

        Shewonk says:
        What government policy in particular? Can you reference some that have specifically referred to the hockey stick or WMO graphic as supporting evidence?

        When the 2001 IPCC report came out with the Hockey Stick of MBH98 as the poster child, the UK government presented it as the evidence that climate change was real. The IPCC Summary for Policymakers claimed it is likely “that the 1990’s has been the warmest decade and 1998 the warmest year of the millenium”
        The Hockey Stick picture was the centre piece of the UK Energy White Paper that was based on the IPCC report. And as a consequence in 2003 the following words were uttered:
        “Climate change – largely caused by burning fossil fuels – threatens major consequences in the UK and worldwide….We need urgent global action to tackle climate change.” by the Rt Hon Tony Blair, then UK Primeminister.

        It was the hockey stick in IPCC 2001 that set the UK government policy to this day. It was the Hockey Stick that allowed the claim that the 1990’s were the hottest decade of the last 1000 years. That claim is not true.

      • I can pretty much guarantee you that the government did not use that graphic as the reason for enacting legislation. Science is often used to inform policy, but usually it is not the only consideration. There are multiple conflicting interests to consider when developing policy. The decision to act is not premised on a single graphic or even on a single document.

        Sadly people are as unaware of how policy works as they are science.

      • You may be right that it wasn’t the sole reason. But it was a very iconic and very powerful image. Which are things that politicians in general are very amenable to.

        Tony Blair was especially moved by and persuaded by such things. And was good at conjuring them in his words as well. He had Brown to do the sums and the detail while he concentrated on the broad brush. I ‘m sure that he was much taken with the graph.

        Thanks for telling us how policy is made btw. We’d never have known otherwise. I’ve always thought that the Queen told Mrs Obama what to instruct BO to do. Have I got it wrong?

      • Glad to help!

        Ignorance is bliss, but it’s a pretty bad basis for policy.

      • shewonk,

        You’re clearly both intelligent and well informed. Have a look at TAR and tell me that the NBH98 graph wasn’t presented as the ‘must use’ icon from the whole document. I would have been incredibly surprised if the various under secretaries – and journalists – hadn’t rushed to the photocopier…..OK, the PDF printer, to make this important information available, both as a news articlce and as an influential policy document.

        If a scientific assessment report is presented in such an unequivocal and visually attractive way, you must surely understand that politicians would only weigh its value against the likelihood of it being either (a) popular with the electorate…..or (b) neutral with the electorate but cash positive for the government. It is only the new – and very cool in a rather anarchic way – medium of the web that has caused diverse views to percolate down to citizen level, in spite of political and journalistic enterprise.

        Politicians deal with multiple lines of policy pressure from any number of sources. You imagine that the process is far more diligent than it actually is, than it actually can be, in reality. This is not because policy makers are lazy and don’t care – it’s because they are human beings and run out of time.

        Clearly you have a real fire in you about this subject. You could do worse than write to your local MP or, better still, a government minister with your views. I think, if you express yourself as clearly as you have here, you may be surprised by the response.

      • Politicians deal with multiple lines of policy pressure from any number of sources. You imagine that the process is far more diligent than it actually is, than it actually can be, in reality. This is not because policy makers are lazy and don’t care – it’s because they are human beings and run out of time.

        Saaad, there is reality, there is our understanding of that reality, there is communication of our understanding of that reality, and our decisions made based on that communication of our understanding of that reality. In each step, some of the reality is lost in translation. It’s inevitable. No science is completely certain and no policy is driven solely based on the science.

        Policy is premised — or should be — on the best available science but as you say, there are conflicting interests to manage. Scientists who seek to communicate their understanding of the state of the science to the public or policy makers must consider their audience. That is a fundamental of communications. If you don’t, communication doesn’t occur. Confusion does.

        Could the WMO graphic have been better referenced or explained or depicted? Perhaps, but I am not the one to determine what would have been the best depiction and besides, it’s a small point in the greater scheme of things and for those who claim to be concerned about AGW. That people make more of it suggests to me that it is due to their hopes they can use it for other purposes.

        For some audiences, you give the full-meal-deal and include all the caveats and provisos. For others, not so much because they either can’t understand their significance or don’t want to understand (just the facts, ma’am) or will become utterly confused by the detail. Policy makers usually employ experts to winnow down all the evidence into something that is actionable. They want the facts and risks and options.

        One graphic may have a lot of impact on a visceral sense, but I can guarantee you that those scientists (and non-scientists) advising policy makers take what the scientists write in their papers and in their public communications and craft it — edit it down — to pull out the key points, messages, in order to suit the goals, values and agendas of the political decision makers. And political decision makers decide whether to act — or not — on whatever basis they find most compelling. No matter how carefully scientists craft their communications, political decision makers and their advisors will take it and do with it as they will in order to decide how and if to act.

        A single graphic alone will not be enough to sway policy makers into acting. If that was the case, we’d have long ago had a carbon tax / cap and trade system, global treaty, comprehensive alternative energy program, and have been well on the way to mitigating CO2.

        I see that WMO graphic as the scientists trying to put together a simple graphic that expressed the best science that was available at the time. Scientists are aware of the caveats and complexity, but if you are asked to condense the current state of the science down into a simple graphic, you can’t by definition include all the complexity. How much complexity to include is a judgement call based on the best science understanding of the time in the expert opinions of the scientists. I refuse to think that I have the expertise to arbitrate this.

        Take the model of the atom and how it has changed over the years. As knowledge progressed, we had different depictions of the atom. The simple model of the atom condenses down an awful lot of information, maths, and uncertainty and evidence into something simple and powerful. Does it fully and perfectly replicate reality? No — it’s meant to abstract from the complexity and give the take home. Just because the older models are imprecise or proven not complete or even incorrect does not mean that those who created the model were intentionally hiding information to deceive.

        That’s what the WMO graphic is, at least in my opinion.

      • The U.S.’s EPA relied almost exclusively on the IPCC literature for their recent finding that CO2 is a pollutant.

      • Considering that IPCC literature is “the” authoritative literature on the subject, that makes sense.

      • Well, yes, of course, they’re the ones that gave us such wonderful contrivances as this little graph we’re discussing. I would mention the other glaring deficiencies that call into question the validity of assigning the word “authoritative” to it, but I think the discussion as devolved enough.

        But, it should suffice that this little sidebar should underscore why it is incumbent upon climatologists to be clear and concise. The graph in question failed miserably in the “clear” department and “concise” isn’t a word I’d attach to it either.

      • This is why the ‘shaft’ of the hockey stick is so important. There is plenty of statistical evidence to suggest that the uncertainties in MBH98 – and all subsequent paleo reconstructions of the MWP – are so large as to make them little better than background noise.

        Z

        Then why do denialists insist that the MWP was as warm or warmer than today, given that you insist that all paleo reconstructions of the MWP are so uncertain as to be little better than background noise?

      • dhogaza,

        Personally I would be happy if we could base any policy decisions on evidence that was much more certain than the paleo reconstructions.

      • > Then why do denialists insist that the MWP was as warm or
        > warmer than today, given that you insist that all paleo reconstructions
        > of the MWP are so uncertain as to be little better than background noise?

        Written testimony of the time. We know for a fact there were vineyards as
        far north as Leeds in England, things must have been considerably warmer
        than now. This situation must have existed for a lengthy period of time
        for anyone to think it worth their while planting vines.

        This is one local example (of many geographically distributed examples)
        but it’s unlikely to have lasted as long as it did if it wasn’t at least a whole
        Northern Hemishpere condition, and as such it should be picked up
        in the paleo reconstrustions.

        Nial.

      • Phil. Felton

        Nial | February 23, 2011 at 5:58 am | Reply
        Written testimony of the time. We know for a fact there were vineyards as far north as Leeds in England, things must have been considerably warmer than now. This situation must have existed for a lengthy period of time for anyone to think it worth their while planting vines.

        That particular ‘fact’ isn’t quite as firm as you make it sound, and most of the vineyards that there are good documentary evidence for (e.g. in the Domesday book) are much further south than Leeds. Why you would think that would mean that it must have been “considerably warmer than now”, since there are more vineyards in England now than then, one even in Leeds (Kirkstall, where the abbey would be likely to have been the site of any winemaking in Leeds)!

      • There are historical records and other evidence that doesn’t rely on tree rings.

      • And they do not show the hockey stick.

      • Yes they do

      • Examples please?

      • I’ll follow hunter’s approach on this one and just state my opinion as fact – if it’s OK for him then it’s OK for me.

      • I’ll give your opinion due weight.

      • dhogza,
        By the way, each time you use ‘denialist’, you lose.

      • Dr Curry uses denialist.

      • i don’t use denialist, but i do use denier, but not in labeling an individual that does not want to be labeled in this way.

      • Right. Calling someone a denialist is far, far worse than comparing them to a eugenicist.

        I mean, seriously… whining about namecalling? Are we in kindergarten? There’s no crying in baseball.

      • Well, on the one had, the eugenicists and the warmist hysterics have one overwhelmingly powerful characteristic in common: Both were calling for radical government action on the basis of scientific evidence and theory that was highly uncertain at best and complete junk at worst.

        Drawing attention to this similarity may or may not constitute “name calling”, but it is at the very least an interesting parallel.

      • because people during the MWP with iron age technology lived and farmed areas of Greenland for several centuries, areas that are now ice covered and which even with modern technology would be nigh on uninhabitable now

      • Yeah, but did they grow strawberries?

        And how do you know they farmed areas that are now under ice?

        Making stuff up out of whole cloth.

        I could point to links showing where the Vikings were and where the ice is now, but you should do your own research.

      • I’ve even heard it argued that it was called Greenland becuase it was such as green and pleasant land when the truth is that was a huge propaganda exercise to persuade vikings to move there. They did and tried to scratch out a living before almost all died off (only coastal settlements survived).

      • Please point out these links. It makes your argument so much more persuasive.

        Because telling people to do their own research doesn’t build confidence that

        a. such links exist and that you are tolerably familiar with them or

        b. that you are genuinely seeking to persuade people of your argument.

        Those not convinced of either a. or b. might be inclined to discount your postings entirely as posturing hot air without substance.

      • I did – long ago. The Greenland Norse settlements were a thriving enterprise for several hundred years with constant trade with the northern European countries. They even acquired their own Bishop, which is an indicator of the size of the communities.

        The settlements died out because of increasing cold, which caused shorter growing seasons and, more importantly, cutoff access to the mainland and Iceland due to the icepack growth. Between 1350 and 1380 AD, the icepack grew such that Greenland Polar Bears were crossing the ice to Iceland, something that hadn’t happened in over 400 years.

        Cut off from trade with the mainland for much of the year, they could not get some of the necessities of life and the settlements gradually died out as the people went back to the “home country”. One of the problems with the settlements was that they never adopted the fishing, hunting and survival techniques of the Inuit, but rather kept on using the European techniques.

        Lots more in any good archaeology text on the subject. For an easy read, try Brian Fagan’s book – “The Little Ice Age”.
        Try some education – it’s a wonderfu thing.

      • The farms of the vikings are not ice-covered today, and they have never been in the years between. And they are still green in the summer.

      • If you read the entire link, it certainly refers to cooling, shorter summers by in the 1300s:

        ‘Greenland’s climate began to change as well; the summers grew shorter and progressively cooler, limiting the time cattle could be kept outdoors and increasing the need for winter fodder. During the worst years, when rains would have been heaviest, the hay crop would barely have been adequate to see the penned animals through the coldest days. Over the decades the drop in temperature seems to have had an effect on the design of the Greenlanders’ houses. Originally conceived as single-roomed structures, like the great hall at Brattahlid, they were divided into smaller spaces for warmth, and then into warrens of interconnected chambers, with the cows kept close by so the owners might benefit from the animals’ body heat.’

        This was added to soil erosion and sociological factors in this analysis of the failure of the Greenland Viking colonies. Must of the standard histories with which I am familiar prioritize the falling temperatures as the key factor which killed these settlements.

      • Which, if you read the sources of that text, may have been corresponding to other known times of a couple of hard winters in a row. Nothing that equals a climate change, but a local phenomena that could easily have been the straw that killed these very exposed settlements.

        (That it actually was the cold temperature that killed of the settlements is the most common explanation, but not the only one, and not one that by any means is proven.)

      • Which, if you read the sources of that text, may have been corresponding to other known times of a couple of hard winters in a row. Nothing that equals a climate change, but a local phenomena that could easily have been the straw that killed these very exposed settlements.

        Horse puckey.

        The original sources were the written records kept by the priests. And the cold was NOT a couple years as you claim. Nor was it a localized phenomena – all of Europe also got cold. AND the evidence is that most of the rest of the planet did as well.

        If you’re reading “other explanations” then you’re reading revisionist texts that are based on uninformed speculation, not original sources.

      • Maybe in the US you all believe that written European history started in about 1776 (to pick a date at random). And that before that people spoke only in grunts and writing was unknown.

        There is a wealth of surviving written material that directly and indirectly supports the conventional view of a cooling period in the 1300s followed by a very welcome warmer time when crops returned to abundance and more. And the population expanded.

        Not only did people write about the weather, you can see it all in their household accounts, their crop inventories, their laws, their rent rolls.

        Medieval times are not a closed book. We know a great deal about that time and its climate from contemporary accounts.

      • LOL

        So the real temperature increases arent there?

      • They most definitely are there, ianash. They just don’t look quite so scarily dramatic when removed from the MBH98 graph.

      • Steven Sullivan

        Why would they be ‘removed’? We have actual temperature data for all of the period of the ‘blade’.

        If in fact there was a MWP model that matched or exceeded the heights reached by the blade…and btw, there isn’t; even with alternate reconstructions, there still a ~0.5 degree gap…that would indicate that climate sensitivity to natural forcings is likely on the HIGH side. And for the we’re adding significant anthropogenic forcings to the mix. Is that good news to you?

      • What government policy in particular? ….

        Look at the bigger picture :
        – CAGW theory is funded by the state
        – CAGW justifies an expansion of the state

        Add to this Climategate and the general rampant dishonesty of the state’s Team, and what do you get?

      • CAGW = State Expansion = conspiracy theory = don’t forget to put on your tinfoil hat

      • So you don’t think CAGW is a reality?

      • Steven Sullivan

        The acronym ‘CAGW’ is a red rag that skeptics wave at each other. It’s also their clumsy way of trying to control the terms of debate.

        You won’t see it much in scientific literature.

      • Have massive power grabs by elites in the past ever been a legitimate cause for concern? Power over the emission of CO2, as Lindzen pointed out long ago, is the ultimate tool for the totalitarian. Pointing this out is not saying that everyone concerned is a totalitarian. Just that history tells us – and I know for past interactions you have these concerns about the rise of the Nazi state – to be extremely careful.

      • intrepid_wanders

        Is that a peer reviewed journal? If not, why not?

        Wow, that seems to remind me of the opening statements that “Policy-Lass” used to get ignored by Steve M. many moons ago. Hope it is working better this time ;) Times may change, but policies remain…

      • “From what I have read, the MWP is thought to be a regional or hemispheric phenomenon. ”

        Try a little more research! Plenty of papers supporting the MWP as worldwide.

      • Pete H, there are papers that dispute the existence of a global MWP and papers that claim it exists. Which plenty do I trust?

      • In instances like that, you can find sources other than climate papers.
        For example, look up some history books. Find out what people were wearing. See if the period was a time of plenty (usually means warm) or a time of hunger, sickness and upheaval ( usually means cool)

      • There is a third way, which is to question the concept or practical usefulness of global temperature. As Dr Curry said above:

        I’m more interested in the handle than the blade of the hockey stick. I also view understanding regional climate variations as much more important than trying to use some statistical model to create global average anomalies (which I personally regard as pointless, given the sampling issue).

        The sampling issues are hard enough even with modern thermometers. With proxies like tree rings, ice cores or coral they are ridiculously hard right now.

        What we are left with, apart from proxies, is plenty of documentary evidence of a warm period in the middle ages across much of the world that was bothering to write such stuff down for posterity. Judith is saying the arguments beyond that may not be worth having – and I agree with her.

        But this also serves to show that simply counting the number of citations on ‘two sides’ of an issue may be quite dumb. Science depends on real data, not the words people write about it. Critical assessment, as always, is required from the reader.

      • Don’t trust any of them. TRY to keep an open mind until there is sufficient unrefuted evidence supporting one side.

        More importantly, do NOT make ANY policies which affect millions of people’s livelihoods and lifestyles until the evidence is unrefuted.

  36. From 1047485263.txt, March 12, 2003

    Can we not address the misconceptions by finally coming up with definitive dates for the LIA and MWP and redefining what we think the terms really mean? With all of us and more on the paper, it should carry a lot of weight. In a way we will be setting the agenda for what should be being done over the next few years.

    My em-ing

  37. charles the moderator

    Wow,

    Watching Gavin sputter is a great early birthday present. Thank you Judith.

    ~ ctm

    (this comment probably shouldn’t survive moderation, and I should know!)

  38. I’m surprised Gavin’s comment didn’t end up in the “Bore Hole.”

    Oops. Sorry, wrong blog.

    BTW, I think the “Bore Hole” is the best bit of that other site.

    • You would orkneygal.

      How you going reading those papers. Worked out where you went wrong yet?

      • By the way, have you read them?

      • Have you?

      • After you, dear friend.

      • Yes, I have read those contradictory papers, carefully. Anyone that does, immediately realizes that the contractions apparent in the respective precipitation maps, generated per methods described, cannot possibly be described as anything other than non-concordant and contradictory.

        Now that the most recent Nature paper has been shown to be fundamentally and fatally flawed, the contradictions of the two papers is less interesting. The Nature paper is technically wrong and wrong headed, so it really doesn’t contradict the view that increasing temperatures are bound to cause increased drought in the mid-latitudes of the NH, which is what the paper that Trenberth approved claims. NH flooding cannot be attributed to climate change, per the Trenberth approved paper. It must therefore be weather.

        A close reading of postings in the Bore Hole gives great insight into the attitude, mentality and biases of the moderators, doesn’t it?

      • As steve mosher said a while back, RC does have some very worthy scientific threads, which have been completely undermined by their overbearing moderation. I gave up reading the comments there a long while ago.
        …but the borehole – IMO, It’s by far the most interesting thing to have happened on RC in recent times (possibly ever), although I think it reveals more about the insecurities of the blog posters than those who are chosen to protect them via moderation.

  39. Wow, Dr. Curry, I’m impressed and a bit disappointed at the same time. I’m impressed with your statement. I’m a bit disappointed with some of your readership. McShane and Wyner pretty much make this discussion …..academic, yet no mention, strange. So perhaps this is what academics do. I think it is good to discuss this. Gavin seems to be in a state of denial. (Sorry, I looked for a better word, but couldn’t find one.) Whether intentional or not, the graph was misleading. It misled a great many people. Gavin, it isn’t ok to mislead people regarding information to our policy makers. It isn’t acceptable. Policies have been changed, in part, based upon the interpretation of that insidious graph. Why? Because some wanted to “tell a story”. I think that’s just about the proper way to term it.

    By this tree ring, I pronounce the average decadal temp 500-490 years ago to be precisely 0.6 C less than today…………….anyone that ever bought into that……..

  40. Very impressive, Judith. It’s nice to see a climate scientist accept and even defend the straightforward interpretation of ‘hide the decline’.

  41. WOW!!
    I am a non-scientist who comes to sites such as this one for enlightenment on the issue. Tonight I get not only enlightenment but the Friday Night Fights as well!

    This is a great discussion Dr. Curry and I am glad Gavin stopped by to participate. His comments were very illuminating in both tone and “content.”

    By the way, Dr. Schmidt, while you are here: do my taxpayer dollars pay for any of your “Real Climate” activities and if not, is that documented somewhere?

  42. Heartening to see your stance on this Dr. Curry, thank you for being so direct. I have been both a scientist (PhD CME) and a marketeer in my career. In neither of these extremes is what was done in that chart either ethical or acceptable.

  43. Judith,

    You write:

    “Can anyone defend “hide the decline”? I would much prefer to be wrong in my interpretation, but I fear that I am not.”

    Thank you for the bravery of the post, considering your pseudo-‘peers’ have no stomach for truth in this instance.

    SteveM deserves credit for disseminating this issue, he also deserves credit for calling my attention to Mann 08. This exact issue was discussed at the Air Vent vociferously in this unique post well before it became mainstream knowledge through climategate. There are reasons that the few blogs which received climategate links were chosen.

    http://noconsensus.wordpress.com/2008/10/05/mxd-tree-removal-service-choppin-wood-off-a-hockey-stick/

    The link is the same discussion that ‘hide the decline’ became famous for – note the date. Same issue, same problem, and if you don’ t snip it, the same kind of falsified methods. — by some of the same people.

    Ducks are Ducks.